Advisories ยป MGASA-2015-0195

Updated glibc packages fix security vulnerabilities

Publication date: 06 May 2015
Type: security
Affected Mageia releases : 4
CVE: CVE-2013-7423 , CVE-2014-8121 , CVE-2015-1781


Updated glibc package fixes security vulnerabilities:

It was discovered that, under certain circumstances, glibc's getaddrinfo()
function would send DNS queries to random file descriptors. An attacker
could potentially use this flaw to send DNS queries to unintended
recipients, resulting in information disclosure or data loss due to the
application encountering corrupted data. (CVE-2013-7423)

It was found that the files back end of Name Service Switch (NSS) did not
isolate iteration over an entire database from key-based look-up API calls.
An application performing look-ups on a database while iterating over it
could enter an infinite loop, leading to a denial of service.

A buffer overflow flaw was found in the way glibc's gethostbyname_r() and
other related functions computed the size of a buffer when passed a
misaligned buffer as input. An attacker able to make an application call
any of these functions with a misaligned buffer could use this flaw to
crash the application or, potentially, execute arbitrary code with the
permissions of the user running the application. (CVE-2015-1781)

Joseph Myers discovered strxfrm is vulnerable to integer overflows
when computing memory allocation sizes (similar to CVE-2012-4412)
[BZ #16009] (CVE pending)

Shaun Colley discovered strxfrm falls back to an unbounded alloca if
malloc fails making it vulnerable to stack-based buffer overflows
(similar to CVE-2012-4424) [BZ #16009] (CVE pending)

A buffer overflow flaw was found in libio/wstrops.c:_IO_wstr_overflow 
wich allows for overflow in calculating the new size in wide characters,
but not for overflow in the multiplication to compute the size in bytes,
which could thus overflow and result in a buffer overrun copying data
into the new buffer. [BZ #17269] (CVE pending)

When processing certain malformed patterns, fnmatch can skip over the
NUL byte terminating the pattern.  This can potentially result in an
application crash if fnmatch hits an unmapped page before encountering a
NUL byte. [BZ #18032] (CVE pending)

Other fixes in this update:
nscd package was missing the /var/db/nscd directory wich prevented
it to work properly (mga#15545).