| Summary: | <sys-libs/cracklib-2.9.6-r1: Stack-based buffer overflow when parsing large GECOS field | ||
|---|---|---|---|
| Product: | Gentoo Security | Reporter: | Agostino Sarubbo <ago> |
| Component: | Vulnerabilities | Assignee: | Gentoo Security <security> |
| Status: | RESOLVED FIXED | ||
| Severity: | major | CC: | base-system |
| Priority: | Normal | ||
| Version: | unspecified | ||
| Hardware: | All | ||
| OS: | Linux | ||
| URL: | http://www.openwall.com/lists/oss-security/2016/08/16/2 | ||
| Whiteboard: | A2 [glsa cve] | ||
| Package list: | Runtime testing required: | --- | |
Bumped revision with cherry-picked https://github.com/cracklib/cracklib/commit/47e5dec521ab6243c9b249dd65b93d232d90d6b1 and https://github.com/cracklib/cracklib/commit/33d7fa4585247cd2247a1ffa032ad245836c6edb: > commit aac5b4f4a65ce70854e77014fa096b7bd2d34e43 > Author: Thomas Deutschmann > Date: Wed Sep 14 22:55:05 2016 +0200 > > sys-libs/cracklib: Revision bump to address CVE-2016-6318 and another buffer overflow > > Signed-off-by: Lars Wendler > Gentoo-Bug: https://bugs.gentoo.org/591456 > > Package-Manager: portage-2.3.0 > @ Arches, please test and mark stable: =sys-libs/cracklib-2.9.6-r1 Stable targets: alpha amd64 arm hppa ia64 ppc ppc64 x86 sparc amd64 stable Stable on alpha. Stable for HPPA PPC64. arm stable x86 stable sparc stable ppc stable ia64 stable. Maintainer(s), please cleanup. Security, please add it to the existing request, or file a new one. cleaned up GLSA created. This issue was resolved and addressed in GLSA 201612-25 at https://security.gentoo.org/glsa/201612-25 by GLSA coordinator Aaron Bauman (b-man). |
From ${URL} : A security flaw was reported to us by CSG Labs, details as follows: A stack-based overflow was found in the way cracklib, a library used to stop users from choosing easy to guess passwords, handled large GECOS field in the /etc/passwd file. When an application compiled against the cracklib libary, such as "passwd" is used to parse the GECOS field, it could cause the application to crash or execute arbitary code with the permissions of the user running such an application. To trigger the flaw, you need a specially-crafted "long" GECOS field, which can be done by a local user on the system. The attacker then needs to run some utility which uses cracklib to process this long GECOS field on the system. (such as "passwd" application which runs suid root) All versions of the cracklib library shipped with Red Hat Enterprise Linux are compiled with FORTIFY_SOURCE, which detects the buffer-overflow and aborts the application safely. Therefore the maximum impact of this flaw is application crash. However, there may be other applications, distributions which dont compile cracklib with FORTIFY_SOURCE, and this can lead to easy code exec or even privsec. A proposed patch is available at: https://bugzilla.redhat.com/attachment.cgi?id=1188599 This flaw was assigned CVE-2016-6318 and it was previously disclosed via linux-distros mailing list. @maintainer(s): after the bump, in case we need to stabilize the package, please let us know if it is ready for the stabilization or not.