Package: mutt Version: 1.5.13-3 Severity: normal Tags: security Mutt, in its parsing of "mailto:" URLs, in some situations writes after the end of a fixed-size buffer. I'm not sure it is exploitable, because the data being written is not attacker-controlled (only a null character), but I'd rather someone more expert than me at security took a look at it.
It happens in file url.c, function url_parse_mailto, in the else block of the very last "if" of the file: if (!ascii_strcasecmp (tag, "body")) { if (body) mutt_str_replace (body, value); } else { taglen = strlen (tag); /* mutt_parse_rfc822_line makes some assumptions */ snprintf (scratch, sizeof (scratch), "%s: %s", tag, value); scratch[taglen] = '\0'; value = &scratch[taglen+1]; SKIPWS (value); mutt_parse_rfc822_line (e, NULL, scratch, value, 1, 0, 0, &last); } scratch is declared like that: char scratch[HUGE_STRING]; where (in lib.h): # define HUGE_STRING 5120 The line scratch[taglen] = '\0'; will write past the end of "scratch". To trigger that, pass as argument to mutt: mailto:[EMAIL PROTECTED] I propose to add: if (taglen > sizeof (scratch)) taglen = sizeof (scratch) - 2 as a safety. -- System Information: Debian Release: lenny/sid APT prefers unstable APT policy: (500, 'unstable'), (1, 'experimental') Architecture: amd64 (x86_64) Kernel: Linux 2.6.18-3-amd64 (SMP w/2 CPU cores) Locale: LANG=fr_LU.UTF-8, LC_CTYPE=fr_LU.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/bash Versions of packages mutt depends on: ii exim4 4.67-1 metapackage to ease exim MTA (v4) ii exim4-daemon-heavy [mail 4.67-1 exim MTA (v4) daemon with extended ii libc6 2.5-9 GNU C Library: Shared libraries ii libdb4.4 4.4.20-8 Berkeley v4.4 Database Libraries [ ii libgnutls13 1.6.2-2 the GNU TLS library - runtime libr ii libidn11 0.6.5-1 GNU libidn library, implementation ii libncursesw5 5.6-3 Shared libraries for terminal hand ii libsasl2-2 2.1.22.dfsg1-10 Authentication abstraction library Versions of packages mutt recommends: ii locales 2.5-9 GNU C Library: National Language ( ii mime-support 3.39-1 MIME files 'mime.types' & 'mailcap -- no debconf information -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]