GNU C Library up to 2.29 Regular Expression posix/regexec.c check_dst_limits_calc_pos_1 resource management

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.2$0-$5k0.00

A vulnerability was found in GNU C Library up to 2.29 (Software Library) and classified as problematic. Affected by this issue is the function check_dst_limits_calc_pos_1 of the file posix/regexec.c of the component Regular Expression Handler. The manipulation with an unknown input leads to a resource management vulnerability. Using CWE to declare the problem leads to CWE-399. Impacted is availability. CVE summarizes:

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 '(\227|)(\\1\\1|t1|\\\2537)+' in grep.

The bug was discovered 01/20/2019. The weakness was released 02/26/2019 (Website). The advisory is shared for download at securityfocus.com. This vulnerability is handled as CVE-2018-20796 since 02/25/2019. 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. The exploit is available at vuldb.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 37 days. During that time the estimated underground price was around $0-$5k. The code used by the exploit is:

(\227|)(\\1\\1|t1|\\\2537)+

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

Entries connected to this vulnerability are available at 131215 and 131217.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Resource management
CWE: CWE-399 / CWE-404
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

01/20/2019 🔍
02/25/2019 +36 days 🔍
02/26/2019 +1 days 🔍
02/26/2019 +0 days 🔍
07/19/2023 +1604 days 🔍

Sourcesinfo

Vendor: gnu.org

Advisory: K26346590
Status: Not defined
Confirmation: 🔍

CVE: CVE-2018-20796 (🔍)
SecurityFocus: 107160

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 02/26/2019 09:35
Updated: 07/19/2023 18:02
Changes: 02/26/2019 09:35 (63), 05/13/2020 06:22 (3), 07/19/2023 18:02 (5)
Complete: 🔍

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