CVE Database


Impact: Low
Public: 2010-12-07
Bugzilla: 645859: CVE-2010-4051 CVE-2010-4052 glibc: De-recursivise regular expression engine


The MITRE CVE dictionary describes this issue as:

The regcomp implementation in the GNU C Library (aka glibc or libc6) through 2.11.3, and 2.12.x through 2.12.2, allows context-dependent attackers to cause a denial of service (application crash) via a regular expression containing adjacent bounded repetitions that bypass the intended RE_DUP_MAX limitation, as demonstrated by a {10,}{10,}{10,}{10,}{10,} sequence in the proftpd.gnu.c exploit for ProFTPD, related to a "RE_DUP_MAX overflow."

Find out more about CVE-2010-4051 from the MITRE CVE dictionary and NIST NVD.


Red Hat does not consider crash of client application, using regcomp()
or regexec() routines on untrusted input without preliminary checking
the input for the sanity, to be a security issue (the described deficiency
implies and is a known limitation of the glibc regular expression engine
implementation). The expressions can be modified to avoid quantification
nesting, or program modified to limit size of input passed to regular
expression engine. We do not currently plan to fix these flaws. If more
information becomes available at a future date, we may revisit these issues.

CVSS v2 metrics

NOTE: The following CVSS v2 metrics and score provided are preliminary and subject to review.

Base Score: 2.1
Base Metrics: AV:L/AC:L/Au:N/C:N/I:N/A:P
Access Vector: Local
Access Complexity: Low
Authentication: None
Confidentiality Impact: None
Integrity Impact: None
Availability Impact: Partial

Find out more about Red Hat support for the Common Vulnerability Scoring System (CVSS).

Red Hat security errata

Platform Errata Release Date

External References

This page is generated automatically and has not been checked for errors or omissions.

For clarification or corrections please contact the Red Hat Security Response Team.