GNU C Library up to 2.27 Regular Expression posix/regcomp.c parse_reg_exp data processing

Summaryinfo

A vulnerability was found in GNU C Library up to 2.27. It has been rated as critical. The impacted element is the function parse_reg_exp of the file posix/regcomp.c of the component Regular Expression Handler. This manipulation causes data processing. This vulnerability is registered as CVE-2009-5155. Remote exploitation of the attack is possible. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in GNU C Library up to 2.27 (Software Library) and classified as critical. Affected by this vulnerability is the function parse_reg_exp of the file posix/regcomp.c of the component Regular Expression Handler. The manipulation with an unknown input leads to a data processing vulnerability. The CWE definition for the vulnerability is CWE-19. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the GNU C Library (aka glibc or libc6) before 2.28, parse_reg_exp in posix/regcomp.c misparses alternatives, which allows attackers to cause a denial of service (assertion failure and application exit) or trigger an incorrect result by attempting a regular-expression match.

The bug was discovered 09/19/2015. The weakness was published 02/26/2019. This vulnerability is known as CVE-2009-5155 since 02/25/2019. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability was handled as a non-public zero-day exploit for at least 1256 days. During that time the estimated underground price was around $0-$5k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 172292 (SUSE Enterprise Linux Security Update for glibc (SUSE-SU-2019:1102-1)).

Upgrading to version 2.28 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 107160†). Similar entries are available at VDB-129978, VDB-131216 and VDB-131217. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Software Library

Vendor

• GNU

Name

• C Library

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16
• 2.17
• 2.18
• 2.19
• 2.20
• 2.21
• 2.22
• 2.23
• 2.24
• 2.25
• 2.26
• 2.27

License

• open-source

Website

• Vendor: https://www.gnu.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

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