| Summary: | <x11-apps/xdm-1.1.11-r3: NULL pointer dereference (DoS) when verifying user credentials in FIPS-140 mode or using >=sys-libs/glibc-2.17 (CVE-2013-2179) | ||
|---|---|---|---|
| Product: | Gentoo Security | Reporter: | Agostino Sarubbo <ago> |
| Component: | Vulnerabilities | Assignee: | Gentoo Security <security> |
| Status: | RESOLVED FIXED | ||
| Severity: | minor | CC: | x11 |
| Priority: | Normal | ||
| Version: | unspecified | ||
| Hardware: | All | ||
| OS: | Linux | ||
| URL: | https://bugzilla.redhat.com/show_bug.cgi?id=973695 | ||
| Whiteboard: | B3 [noglsa] | ||
| Package list: | Runtime testing required: | --- | |
| Bug Depends on: | 475480 | ||
| Bug Blocks: | |||
glibc-2.17 does not exist in the stable tree, and what is "the FIPS-140 mode"? Further info: "Without this fix, if xdm is built to use raw crypt() authentication, instead of a higher level system such as PAM or BSD Auth, and that crypt() function can return a NULL pointer (as glibc 2.17+ does for invalid input, such as when an account is locked by prepending a "!" to the password field), then attempting to login to such an account via xdm can crash the xdm daemon." Thanks for your work. GLSA vote: no CVE-2013-2179 (http://nvd.nist.gov/nvd.cfm?cvename=CVE-2013-2179): X.Org xdm 1.1.10, 1.1.11, and possibly other versions, when performing authentication using certain implementations of the crypt API function that can return NULL, allows remote attackers to cause a denial of service (NULL pointer dereference and crash) by attempting to log into an account whose password field contains invalid characters, as demonstrated using the crypt function from glibc 2.17 and later with (1) the "!" character in the salt portion of a password field or (2) a password that has been encrypted using DES or MD5 in FIPS-140 mode. GLSA vote: no. Closing as [noglsa]. |
From ${URL} : A NULL pointer dereference, leading to denial of service flaw was found in the way X.Org X11 xdm, X.Org X Display Manager, performed user credentials verification, when the FIPS-140 mode was enabled on the underlying Linux system or the xdm was compiled against glibc library of version of 2.17 and above. A local attacker could provide a specially-crafted input that, when processed would lead to xdm executable crash. References: [1] http://www.openwall.com/lists/oss-security/2013/06/11/5 Relevant upstream patch: [2] http://cgit.freedesktop.org/xorg/app/xdm/commit/?id=8d1eb5c74413e4c9a21f689fc106949b121c0117 @maintainer(s): after the bump, in case we need to stabilize the package, please say explicitly if it is ready for the stabilization or not.