GNU C Library up to 2.33 mq_notify sigevent use after free

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability was found in GNU C Library up to 2.33. It has been classified as problematic. This issue affects the function mq_notify. The manipulation of the argument sigevent leads to use after free. This vulnerability is uniquely identified as CVE-2021-33574. No exploit exists.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in GNU C Library up to 2.33 (Software Library). This issue affects the function mq_notify. The manipulation of the argument sigevent with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability.

The weakness was disclosed 05/26/2021. The advisory is shared at sourceware.org. The identification of this vulnerability is CVE-2021-33574. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 266254 (NewStart CGSL MAIN 6.06 : glibc Multiple Vulnerabilities (NS-SA-2025-0229)), which helps to determine the existence of the flaw in a target environment.

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

The vulnerability is also documented in the vulnerability database at Tenable (266254). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.5
VulDB Temp Score: 5.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 266254
Nessus Name: NewStart CGSL MAIN 6.06 : glibc Multiple Vulnerabilities (NS-SA-2025-0229)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

05/25/2021 🔍
05/26/2021 +1 days 🔍
05/26/2021 +0 days 🔍
10/01/2025 +1589 days 🔍

Sourcesinfo

Vendor: gnu.org

Advisory: sourceware.org
Status: Not defined

CVE: CVE-2021-33574 (🔍)
GCVE (CVE): GCVE-0-2021-33574
GCVE (VulDB): GCVE-100-175817

Entryinfo

Created: 05/26/2021 08:41
Updated: 10/01/2025 10:46
Changes: 05/26/2021 08:41 (38), 05/29/2021 10:02 (2), 10/01/2025 10:46 (16)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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