TUCoPS :: Unix :: General :: cert0149.txt

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=============================================================================
CERT* Advisory CA-97.17
Original issue date: May 29, 1997
Last revised: June 9, 1997
 Appendix A - added information from Sun Microsystems, Inc.
 A complete revision history is at the end of this file.
Topic: Vulnerability in suidperl (sperl)
- -----------------------------------------------------------------------------
The CERT Coordination Center has received reports of a buffer overflow
condition in suidperl built from Perl 4.n and Perl 5.n distributions on UNIX
systems. By calling this program with appropriately crafted parameters,
unauthorized local users can execute arbitrary commands as root. This
vulnerability is being actively exploited.
The CERT/CC team recommends installing a vendor patch if one is available (see
Section III.B). Until you can do so, we recommend disabling suidperl (Section
III.A). Two other alternatives are to install suidperl or sperl from version
5.003 source code along with the patch provided in Appendix B of this
advisory (see also Section III.C), or upgrade to Perl version 5.004 (Section
III.D). Note that Perl4 is no longer supported.
We will update this advisory as we receive additional information.
Please check our advisory files regularly for updates that relate to your site.
- -----------------------------------------------------------------------------
I. Description
 On some systems, setuid and setgid scripts (scripts written in the C
 shell, Bourne shell, or Perl, for example, with the set user or group ID
 permissions enabled) are insecure due to a race condition in the
 kernel. For those systems, Perl versions 4 and 5 attempt to work around
 this vulnerability with a special program named suidperl, also known as
 sperl. This program attempts to emulate the set-user-ID and set-group-ID
 features of the kernel.
 There is a buffer overflow condition in suidperl built from Perl 4.n and
 Perl 5.n distributions earlier than version 5.004. If this program is
 called with appropriately crafted parameters, an attacker can execute
 arbitrary commands as root. This vulnerability is being actively
 exploited.
II. Impact
 Users executing Perl scripts with the setuid bit set can execute
 arbitrary commands with the effective uid of the owner of the Perl
 script. Attackers can execute commands as root.
III. Solution
 Use the command in Section A to help you determine if your system is
 vulnerable and, if it is, to (optionally) disable the suidperl and sperl
 programs (see Section A). If you find that your system is vulnerable,
 replace the suidperl and sperl programs with new versions.
 Section B describes how to do that if your site uses versions of suidperl
 and sperl that are provided as part of a vendor-supplied distribution.
 Sites that installed suidperl and sperl programs themselves from the Perl
 source distribution should patch the distribution as described in Section
 C or upgrade to version 5.004 as described in Section D. Note that Perl4
 is no longer supported.
 A. Determine if your system is vulnerable and disable vulnerable programs
 To determine if a system is vulnerable to this problem and to disable
 the programs that are believed to be vulnerable, use the following
 find command or a variant. Consult your local system documentation to
 determine how to tailor the find program on your system.
 After you have run this command on all your systems, they will no
 longer be vulnerable. Note that after disabling the suidperl and sperl
 programs, they will no longer be able to emulate the set-user-ID and
 set-group-ID features of the kernel.
 You will need to run the find command on each system you maintain
 because the command examines files on the local disk only. Substitute
 the names of your local file systems for FILE_SYSTEM_NAMES in the
 example. Example local file system names are /, /usr, and /var.
 You must do this as root.
 Note that this is one long command, though we have separated
 it onto five lines using back-slashes.
 find FILE_SYSTEM_NAMES -xdev -type f -user root \
 \( -name 'sperl4.[0-9][0-9][0-9]' \
 -o -name 'sperl5.00[0-3]' \
 -o -name 'suidperl' \) \
 -perm -04000 -print -ok chmod ug-s '{}' \;
 This command will find all files on a system that are
 - only in the file system you name (FILE_SYSTEM_NAMES -xdev)
 - regular files (-type f)
 - owned by root (-user root)
 - named appropriately (-name 'sperl4.[0-9][0-9][0-9]'
 -o -name 'sperl5.00[0-3]'
 -o -name 'suidperl')
 - setuid root (-perm -04000)
 Once found, those files will
 - have their names printed (-print)
 - have their modes changed, but only if you type `y'
 in response to the prompt (-ok chown ug-s '{}' \;)
 B. Obtain and install the appropriate patch from your vendor
 If your vendor ships suidperl or sperl, you may be vulnerable and need
 a patch. Appendix A contains information provided by the following
 vendors. If your vendor is not on this list, please contact the vendor
 directly.
 Berkeley Software Design, Inc. (BSDI)
 Cray Research - A Silicon Graphics Company
 Data General Corporation
 Hewlett-Packard Company
 IBM Corporation
 Linux
 The Santa Cruz Operation, Inc. (SCO)
 Silicon Graphics, Inc. (SGI)
 Until you can install a patch, we recommend disabling suidperl.
 The find command above will help you do that. If you need
 suidperl or sperl, see the alternatives in Sections C and D below.
 C. Install suidperl or sperl from 5.003 source code and apply a patch.
 Follow the instructions below, which were provided by Chip Salzenberg.
 If you would like to keep using setuid Perl scripts, fix Perl
 yourself by following these steps:
 1. Go to your Perl 5.003 source directory, or else obtain a fresh
 Perl 5.003 distribution from
 http://www.perl.com/CPAN/src/5.0/perl5.003.tar.gz
 or another CPAN archive accessible to you.
 This file is approximately 1.5 megabytes in size.
 2. Using the "patch" program, apply the patch that is enclosed
 below in Appendix B.
 3. Build and install the patched Perl 5.003. (If you have never
 built Perl before, be sure to read the "INSTALL" file first.)
 Perl 5.003 binaries that have had this patch applied, and therefore
 are safe from all known attacks, can be identified by the
 output of the "perl -v" command: the "locally applied patches" list
 will include "SUIDBUF - Buffer overflow fixes for suidperl
 security".
 D. Install suidperl or sperl from 5.004 source code (no patch needed).
 If you would like to upgrade to Perl version 5.004, follow these
 steps:
 1. Obtain a fresh Perl 5.004 distribution from
 http://www.perl.com/CPAN/src/5.0/perl5.004.tar.gz
 or another CPAN archive accessible to you.
 This file is approximately 2.5 megabytes in size.
 2. Build and install Perl 5.004 according to the instructions
 given in the "INSTALL" file. Do NOT apply the patch.
 Perl 5.004 binaries, which are safe from all known attacks, can be
 identified by the output of the "perl -v" command: it should say
 "This is perl, version 5.004". (Unlike the 5.003 patch mentioned
 in Section C, the "locally applied patches" list will NOT include
 "SUIDBUF - Buffer overflow fixes for suidperl security". The fact
 that it is version 5.004 is sufficient in this case.)
...........................................................................
Appendix A - Vendor Information
Below is a list of the vendors who have provided information for this
advisory. We will update this appendix as we receive additional information.
If you do not see your vendor's name, the CERT/CC did not hear from that
vendor. Please contact the vendor directly.
Berkeley Software Design, Inc. (BSDI)
=====================================
 BSD/OS is vulnerable to the suidperl (sperl) buffer overflow problem. We
 will be releasing a patch for BSDI 3.0 and perl 5.003 and are currently
 working on patches for BSD/OS 3.0 and Perl 4.036. We will also be developing
 patches for the perl versions shipped with BSD/OS 2.1.
Cray Research - A Silicon Graphics Company
==========================================
 Cray Research does not ship perl as part of either Unicos or Unicos/mk.
Data General Corporation
========================
 The only perl executables that are shipped with DG/UX are:
 /bin/perl
 and
 /bin/perl5 /* in R420 */
 These are not set uid programs.
 Therefore,
 No versions of DG/UX are vulnerable to this problem.
Hewlett-Packard Company
=======================
 HP does not ship this product.
IBM Corporation
===============
 AIX versions do not have Perl as part of the standard product.
 However, the SP2's PSSP software does contain suidperl, but the
 program is not installed with the setuid bit set.
 IBM and AIX are registered trademarks of International Business Machines
 Corporation.
Linux
=====
 Red Hat 4.2 is not vulnerable
 Red Hat 4.1/4.0 you can get the upgraded RPM from ftp.redhat.com
 If you wish to check whether you have the fixed perl run perl -v and
 check for
 Locally applied patches:
 SUIDBUF - Buffer overflow fixes for suidperl security
The Santa Cruz Operation, Inc. (SCO)
====================================
 suidperl is not included in any SCO products.
 SCO CMW+ and SCO OpenServer do not have kernel support for setuid
 scripts, but you may have installed suidperl in order to emulate
 that functionality - in that case you should replace your version of
 perl with version 5.004, or patch your source code as noted in this
 advisory.
 SCO UnixWare does have safe kernel support for setuid scripts so
 that suidperl is not necessary. If you have installed a version
 of perl that includes suidperl, you should remove suidperl and
 install a version of perl built so as not to require it.
Silicon Graphics, Inc. (SGI)
=============================
 At this time, Silicon Graphics does not have any public information for
 this suidperl/sperl issue. Silicon Graphics has communicated with
 CERT and other external security parties and is actively investigating
 this issue. When more Silicon Graphics information (including any
 possible patches) is available for release, that information will
 be released via the SGI security mailing list, wiretap.
 For subscribing to the wiretap mailing list and other SGI security
 related information, please refer to the Silicon Graphics Security
 Headquarters website located at:
 http://www.sgi.com/Support/Secur/security.html
Sun Microsystems, Inc.
======================
Sun does not ship this product.
...........................................................................
Appendix B - Source Code Patch Information
The following patch information has been supplied by Chip Salzenberg. If you
built suidperl or sperl from 5.003 source code, we encouraged you to apply
this patch (see the explanation in Section III.C above).
Patch follows.
- --------------------------------------------------------------------------
Index: patchlevel.h
***************
*** 41,42 ****
- --- 41,43 ----
+ ,"SUIDBUF - Buffer overflow fixes for suidperl security"
 ,NULL
 };
Index: perl.c
*************** char *s;
*** 1212,1216 ****
 # endif
 #endif
! fputs("\n\t+ suidperl security patch", stdout);
 fputs("\n\nCopyright 1987-1996, Larry Wall\n",stdout);
 #ifdef MSDOS
- --- 1212,1216 ----
 # endif
 #endif
! fputs("\n\t+ two suidperl security patches", stdout);
 fputs("\n\nCopyright 1987-1996, Larry Wall\n",stdout);
 #ifdef MSDOS
Index: gv.c
*************** gv_fetchfile(name)
*** 59,67 ****
 char *name;
 {
! char tmpbuf[1200];
 GV *gv;
! sprintf(tmpbuf,"::_<%s", name);
 gv = gv_fetchpv(tmpbuf, TRUE, SVt_PVGV);
 sv_setpv(GvSV(gv), name);
 if (*name == '/' && (instr(name,"/lib/") || instr(name,".pm")))
- --- 59,80 ----
 char *name;
 {
! char smallbuf[256];
! char *tmpbuf;
! STRLEN tmplen;
 GV *gv;
! tmplen = strlen(name) + 4;
! if (tmplen < sizeof smallbuf)
! tmpbuf = smallbuf;
! else
! New(603, tmpbuf, tmplen + 1, char);
! tmpbuf[0] = ':';
! tmpbuf[1] = ':';
! tmpbuf[2] = '_';
! tmpbuf[3] = '<';
! strcpy(tmpbuf + 4, name);
 gv = gv_fetchpv(tmpbuf, TRUE, SVt_PVGV);
+ if (tmpbuf != smallbuf)
+ Safefree(tmpbuf);
 sv_setpv(GvSV(gv), name);
 if (*name == '/' && (instr(name,"/lib/") || instr(name,".pm")))
Index: toke.c
*************** static char *scan_const _((char *start))
*** 22,26 ****
 static char *scan_formline _((char *s));
 static char *scan_heredoc _((char *s));
! static char *scan_ident _((char *s, char *send, char *dest, I32 ck_uni));
 static char *scan_inputsymbol _((char *start));
 static char *scan_pat _((char *start));
- --- 22,27 ----
 static char *scan_formline _((char *s));
 static char *scan_heredoc _((char *s));
! static char *scan_ident _((char *s, char *send, char *dest, STRLEN destlen,
! I32 ck_uni));
 static char *scan_inputsymbol _((char *start));
 static char *scan_pat _((char *start));
*************** static char *scan_str _((char *start));
*** 28,32 ****
 static char *scan_subst _((char *start));
 static char *scan_trans _((char *start));
! static char *scan_word _((char *s, char *dest, int allow_package, STRLEN *slp));
 static char *skipspace _((char *s));
 static void checkcomma _((char *s, char *name, char *what));
- --- 29,34 ----
 static char *scan_subst _((char *start));
 static char *scan_trans _((char *start));
! static char *scan_word _((char *s, char *dest, STRLEN destlen,
! int allow_package, STRLEN *slp));
 static char *skipspace _((char *s));
 static void checkcomma _((char *s, char *name, char *what));
*************** static char * filter_gets _((SV *sv, FIL
*** 47,50 ****
- --- 49,54 ----
 static void restore_rsfp _((void *f));
+ static char too_long[] = "Identifier too long";
+
 /* The following are arranged oddly so that the guard on the switch statement
 * can get by with a single comparison (if the compiler is smart enough).
*************** int allow_tick;
*** 475,479 ****
 (allow_tick && *s == '\'') )
 {
! s = scan_word(s, tokenbuf, allow_pack, &len);
 if (check_keyword && keyword(tokenbuf, len))
 return start;
- --- 479,483 ----
 (allow_tick && *s == '\'') )
 {
! s = scan_word(s, tokenbuf, sizeof tokenbuf, allow_pack, &len);
 if (check_keyword && keyword(tokenbuf, len))
 return start;
*************** register char *s;
*** 847,851 ****
 unsigned char un_char = 0, last_un_char;
 char *send = strchr(s,']');
! char tmpbuf[512];
 if (!send) /* has to be an expression */
- --- 851,855 ----
 unsigned char un_char = 0, last_un_char;
 char *send = strchr(s,']');
! char tmpbuf[sizeof tokenbuf * 4];
 if (!send) /* has to be an expression */
*************** register char *s;
*** 872,876 ****
 weight -= seen[un_char] * 10;
 if (isALNUM(s[1])) {
! scan_ident(s,send,tmpbuf,FALSE);
 if ((int)strlen(tmpbuf) > 1 && gv_fetchpv(tmpbuf,FALSE, SVt_PV))
 weight -= 100;
- --- 876,880 ----
 weight -= seen[un_char] * 10;
 if (isALNUM(s[1])) {
! scan_ident(s, send, tmpbuf, sizeof tmpbuf, FALSE);
 if ((int)strlen(tmpbuf) > 1 && gv_fetchpv(tmpbuf,FALSE, SVt_PV))
 weight -= 100;
*************** GV *gv;
*** 942,946 ****
 {
 char *s = start + (*start == '$');
! char tmpbuf[1024];
 STRLEN len;
 GV* indirgv;
- --- 946,950 ----
 {
 char *s = start + (*start == '$');
! char tmpbuf[sizeof tokenbuf];
 STRLEN len;
 GV* indirgv;
*************** GV *gv;
*** 952,956 ****
 gv = 0;
 }
! s = scan_word(s, tmpbuf, TRUE, &len);
 if (*start == '$') {
 if (gv || last_lop_op == OP_PRINT || isUPPER(*tokenbuf))
- --- 956,960 ----
 gv = 0;
 }
! s = scan_word(s, tmpbuf, sizeof tmpbuf, TRUE, &len);
 if (*start == '$') {
 if (gv || last_lop_op == OP_PRINT || isUPPER(*tokenbuf))
*************** yylex()
*** 1629,1633 ****
 case '*':
 if (expect != XOPERATOR) {
! s = scan_ident(s, bufend, tokenbuf, TRUE);
 expect = XOPERATOR;
 force_ident(tokenbuf, '*');
- --- 1633,1637 ----
 case '*':
 if (expect != XOPERATOR) {
! s = scan_ident(s, bufend, tokenbuf, sizeof tokenbuf, TRUE);
 expect = XOPERATOR;
 force_ident(tokenbuf, '*');
*************** yylex()
*** 1645,1649 ****
 case '%':
 if (expect != XOPERATOR) {
! s = scan_ident(s, bufend, tokenbuf + 1, TRUE);
 if (tokenbuf[1]) {
 expect = XOPERATOR;
- --- 1649,1653 ----
 case '%':
 if (expect != XOPERATOR) {
! s = scan_ident(s, bufend, tokenbuf + 1, sizeof tokenbuf - 1, TRUE);
 if (tokenbuf[1]) {
 expect = XOPERATOR;
*************** yylex()
*** 1748,1752 ****
 s++;
 if (s < bufend && isALPHA(*s)) {
! d = scan_word(s, tokenbuf, FALSE, &len);
 while (d < bufend && (*d == ' ' || *d == '\t'))
 d++;
- --- 1752,1756 ----
 s++;
 if (s < bufend && isALPHA(*s)) {
! d = scan_word(s, tokenbuf, sizeof tokenbuf, FALSE, &len);
 while (d < bufend && (*d == ' ' || *d == '\t'))
 d++;
*************** yylex()
*** 1847,1851 ****
 }
! s = scan_ident(s-1, bufend, tokenbuf, TRUE);
 if (*tokenbuf) {
 expect = XOPERATOR;
- --- 1851,1855 ----
 }
! s = scan_ident(s - 1, bufend, tokenbuf, sizeof tokenbuf, TRUE);
 if (*tokenbuf) {
 expect = XOPERATOR;
*************** yylex()
*** 1956,1960 ****
 case '$':
 if (s[1] == '#' && (isALPHA(s[2]) || strchr("_{$:", s[2]))) {
! s = scan_ident(s+1, bufend, tokenbuf+1, FALSE);
 if (expect == XOPERATOR) {
 if (lex_formbrack && lex_brackets == lex_formbrack) {
- --- 1960,1965 ----
 case '$':
 if (s[1] == '#' && (isALPHA(s[2]) || strchr("_{$:", s[2]))) {
! s = scan_ident(s + 1, bufend, tokenbuf + 1, sizeof tokenbuf - 1,
! FALSE);
 if (expect == XOPERATOR) {
 if (lex_formbrack && lex_brackets == lex_formbrack) {
*************** yylex()
*** 1982,1986 ****
 TOKEN(DOLSHARP);
 }
! s = scan_ident(s, bufend, tokenbuf+1, FALSE);
 if (expect == XOPERATOR) {
 if (lex_formbrack && lex_brackets == lex_formbrack) {
- --- 1987,1991 ----
 TOKEN(DOLSHARP);
 }
! s = scan_ident(s, bufend, tokenbuf + 1, sizeof tokenbuf - 1, FALSE);
 if (expect == XOPERATOR) {
 if (lex_formbrack && lex_brackets == lex_formbrack) {
*************** yylex()
*** 2016,2024 ****
 if (*s == '{' && strEQ(tokenbuf, "$SIG") &&
 (t = strchr(s,'}')) && (t = strchr(t,'='))) {
! char tmpbuf[1024];
 STRLEN len;
 for (t++; isSPACE(*t); t++) ;
 if (isIDFIRST(*t)) {
! t = scan_word(t, tmpbuf, TRUE, &len);
 if (*t != '(' && perl_get_cv(tmpbuf, FALSE))
 warn("You need to quote \"%s\"", tmpbuf);
- --- 2021,2029 ----
 if (*s == '{' && strEQ(tokenbuf, "$SIG") &&
 (t = strchr(s,'}')) && (t = strchr(t,'='))) {
! char tmpbuf[sizeof tokenbuf];
 STRLEN len;
 for (t++; isSPACE(*t); t++) ;
 if (isIDFIRST(*t)) {
! t = scan_word(t, tmpbuf, sizeof tmpbuf, TRUE, &len);
 if (*t != '(' && perl_get_cv(tmpbuf, FALSE))
 warn("You need to quote \"%s\"", tmpbuf);
*************** yylex()
*** 2093,2097 ****
 case '@':
! s = scan_ident(s, bufend, tokenbuf+1, FALSE);
 if (expect == XOPERATOR)
 no_op("Array",s);
- --- 2098,2102 ----
 case '@':
! s = scan_ident(s, bufend, tokenbuf + 1, sizeof tokenbuf - 1, FALSE);
 if (expect == XOPERATOR)
 no_op("Array",s);
*************** yylex()
*** 2129,2133 ****
 : !GvHV(gv) )))
 {
! char tmpbuf[1024];
 sprintf(tmpbuf, "Literal @%s now requires backslash",tokenbuf+1);
 yyerror(tmpbuf);
- --- 2134,2138 ----
 : !GvHV(gv) )))
 {
! char tmpbuf[sizeof tokenbuf + 40];
 sprintf(tmpbuf, "Literal @%s now requires backslash",tokenbuf+1);
 yyerror(tmpbuf);
*************** yylex()
*** 2293,2297 ****
 keylookup:
 bufptr = s;
! s = scan_word(s, tokenbuf, FALSE, &len);
 
 if (*s == ':' && s[1] == ':' && strNE(tokenbuf, "CORE"))
- --- 2298,2302 ----
 keylookup:
 bufptr = s;
! s = scan_word(s, tokenbuf, sizeof tokenbuf, FALSE, &len);
 
 if (*s == ':' && s[1] == ':' && strNE(tokenbuf, "CORE"))
*************** yylex()
*** 2338,2342 ****
 if (*s == '\'' || *s == ':' && s[1] == ':') {
! s = scan_word(s, tokenbuf + len, TRUE, &len);
 if (!len)
 croak("Bad name after %s::", tokenbuf);
- --- 2343,2348 ----
 if (*s == '\'' || *s == ':' && s[1] == ':') {
! s = scan_word(s, tokenbuf + len, sizeof tokenbuf - len,
! TRUE, &len);
 if (!len)
 croak("Bad name after %s::", tokenbuf);
*************** yylex()
*** 2557,2561 ****
 s += 2;
 d = s;
! s = scan_word(s, tokenbuf, FALSE, &len);
 tmp = keyword(tokenbuf, len);
 if (tmp < 0)
- --- 2563,2567 ----
 s += 2;
 d = s;
! s = scan_word(s, tokenbuf, sizeof tokenbuf, FALSE, &len);
 tmp = keyword(tokenbuf, len);
 if (tmp < 0)
*************** yylex()
*** 3244,3250 ****
 if (isIDFIRST(*s) || *s == '\'' || *s == ':') {
! char tmpbuf[128];
 expect = XBLOCK;
! d = scan_word(s, tmpbuf, TRUE, &len);
 if (strchr(tmpbuf, ':'))
 sv_setpv(subname, tmpbuf);
- --- 3250,3256 ----
 if (isIDFIRST(*s) || *s == '\'' || *s == ':') {
! char tmpbuf[sizeof tokenbuf];
 expect = XBLOCK;
! d = scan_word(s, tmpbuf, sizeof tmpbuf, TRUE, &len);
 if (strchr(tmpbuf, ':'))
 sv_setpv(subname, tmpbuf);
*************** char *what;
*** 4091,4102 ****
 static char *
! scan_word(s, dest, allow_package, slp)
 register char *s;
 char *dest;
 int allow_package;
 STRLEN *slp;
 {
 register char *d = dest;
 for (;;) {
 if (isALNUM(*s))
 *d++ = *s++;
- --- 4097,4112 ----
 static char *
! scan_word(s, dest, destlen, allow_package, slp)
 register char *s;
 char *dest;
+ STRLEN destlen;
 int allow_package;
 STRLEN *slp;
 {
 register char *d = dest;
+ register char *e = d + destlen - 3; /* two-character token, ending NUL */
 for (;;) {
+ if (d >= e)
+ croak(too_long);
 if (isALNUM(*s))
 *d++ = *s++;
*************** STRLEN *slp;
*** 4119,4129 ****
 static char *
! scan_ident(s,send,dest,ck_uni)
 register char *s;
 register char *send;
 char *dest;
 I32 ck_uni;
 {
 register char *d;
 char *bracket = 0;
 char funny = *s++;
- --- 4129,4141 ----
 static char *
! scan_ident(s, send, dest, destlen, ck_uni)
 register char *s;
 register char *send;
 char *dest;
+ STRLEN destlen;
 I32 ck_uni;
 {
 register char *d;
+ register char *e;
 char *bracket = 0;
 char funny = *s++;
*************** I32 ck_uni;
*** 4134,4143 ****
 s = skipspace(s);
 d = dest;
 if (isDIGIT(*s)) {
! while (isDIGIT(*s))
 *d++ = *s++;
 }
 else {
 for (;;) {
 if (isALNUM(*s))
 *d++ = *s++;
- --- 4146,4161 ----
 s = skipspace(s);
 d = dest;
+ e = d + destlen - 3; /* two-character token, ending NUL */
 if (isDIGIT(*s)) {
! while (isDIGIT(*s)) {
! if (d >= e)
! croak(too_long);
 *d++ = *s++;
+ }
 }
 else {
 for (;;) {
+ if (d >= e)
+ croak(too_long);
 if (isALNUM(*s))
 *d++ = *s++;
- --------------------------------------------------------------------------
End of patch.
- -----------------------------------------------------------------------------
The CERT Coordination Center staff thanks Chip Salzenberg for supplying a fix,
Larry Wall for tweaking the fix, and Warner Losh for his work on patches.
- -----------------------------------------------------------------------------
If you believe that your system has been compromised, contact the CERT
Coordination Center or your representative in the Forum of Incident Response
and Security Teams (see http://www.first.org/team-info/)
CERT/CC Contact Information
- ----------------------------
Email cert@cert.org
Phone +1 412-268-7090 (24-hour hotline)
 CERT personnel answer 8:30-5:00 p.m. EST(GMT-5) / EDT(GMT-4)
 and are on call for emergencies during other hours.
Fax +1 412-268-6989
Postal address
 CERT Coordination Center
 Software Engineering Institute
 Carnegie Mellon University
 Pittsburgh PA 15213-3890
 USA
Using encryption
 We strongly urge you to encrypt sensitive information sent by email. We can
 support a shared DES key or PGP. Contact the CERT/CC for more information.
 Location of CERT PGP key
 ftp://info.cert.org/pub/CERT_PGP.key
Getting security information
 CERT publications and other security information are available from
 http://www.cert.org/
 ftp://info.cert.org/pub/
 CERT advisories and bulletins are also posted on the USENET newsgroup
 comp.security.announce
 To be added to our mailing list for advisories and bulletins, send
 email to
 cert-advisory-request@cert.org
 In the subject line, type
 SUBSCRIBE your-email-address
- ---------------------------------------------------------------------------
* Registered U.S. Patent and Trademark Office.
Copyright 1997 Carnegie Mellon University
This material may be reproduced and distributed without permission provided
it is used for noncommercial purposes and the copyright statement is
included.
The CERT Coordination Center is part of the Software Engineering Institute
(SEI). The SEI is sponsored by the U.S. Department of Defense.
- ---------------------------------------------------------------------------
This file: ftp://info.cert.org/pub/cert_advisories/CA-97.17.sperl
 http://www.cert.org
 click on "CERT Advisories"
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Revision history
June 9, 1997 Appendix A - added information from Sun Microsystems, Inc.
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