GNU C Library up to 2.29 Regex posix/regexec.c check_dst_limits_calc_pos_1 Pattern resource management ⚔ [Disputed]

Summaryinfo

A vulnerability was found in GNU C Library up to 2.29. It has been declared as problematic. This impacts the function check_dst_limits_calc_pos_1 of the file posix/regexec.c of the component Regex Handler. Such manipulation with the input (|)(\1\1)* as part of Pattern leads to resource management. This vulnerability is listed as CVE-2019-9192. The attack may be performed from remote. In addition, an exploit is available. The real existence of this vulnerability is still doubted at the moment.

Detailsinfo

A vulnerability was found in GNU C Library up to 2.29 (Software Library). It has been rated as problematic. Affected by this issue is the function check_dst_limits_calc_pos_1 of the file posix/regexec.c of the component Regex Handler. The manipulation with the input value (|)(\\1\\1)* leads to a resource management vulnerability. Using CWE to declare the problem leads to CWE-399. Impacted is availability. CVE summarizes:

** DISPUTED ** In the GNU C Library (aka glibc or libc6) through 2.29, check_dst_limits_calc_pos_1 in posix/regexec.c has Uncontrolled Recursion, as demonstrated by '(|)(\\1\\1)*' in grep, a different issue than CVE-2018-20796. NOTE: the software maintainer disputes that this is a vulnerability because the behavior occurs only with a crafted pattern.

The weakness was presented 02/26/2019. This vulnerability is handled as CVE-2019-9192 since 02/26/2019. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details as well as a public exploit are known.

A public exploit has been developed in Regex Pattern. The exploit is available at vuldb.com. It is declared as proof-of-concept. The real existence of this vulnerability is still doubted at the moment. The code used by the exploit is:

(|)(\\1\\1)*

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best 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
• 2.28
• 2.29

License

• open-source

Website

• Vendor: https://www.gnu.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

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CVSSv2info

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Entryinfo

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