GnuTLS lib/ext/pre_shared_key.c client_send_params use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.0$0-$5k0.00

Summaryinfo

A vulnerability identified as problematic has been detected in GnuTLS. Affected by this vulnerability is the function client_send_params in the library lib/ext/pre_shared_key.c. The manipulation leads to use after free. This vulnerability is referenced as CVE-2021-20232. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in GnuTLS (Network Encryption Software) (affected version not known). It has been rated as critical. This issue affects the function client_send_params in the library lib/ext/pre_shared_key.c. The manipulation 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 published 03/13/2021. It is possible to read the advisory at bugzilla.redhat.com. The identification of this vulnerability is CVE-2021-20232. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 236730 (Alibaba Cloud Linux 3 : 0181: gnutls (ALINUX3-SA-2022:0181)), 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 (236730). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.0
VulDB Meta Temp Score: 8.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

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

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 236730
Nessus Name: Alibaba Cloud Linux 3 : 0181: gnutls (ALINUX3-SA-2022:0181)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/17/2020 🔍
03/13/2021 +86 days 🔍
03/13/2021 +0 days 🔍
12/03/2025 +1726 days 🔍

Sourcesinfo

Advisory: bugzilla.redhat.com
Status: Not defined
Confirmation: 🔍

CVE: CVE-2021-20232 (🔍)
GCVE (CVE): GCVE-0-2021-20232
GCVE (VulDB): GCVE-100-171215

Entryinfo

Created: 03/13/2021 07:41
Updated: 12/03/2025 17:08
Changes: 03/13/2021 07:41 (37), 04/01/2021 01:19 (2), 04/01/2021 01:22 (18), 05/16/2025 13:43 (16), 12/03/2025 17:08 (1)
Complete: 🔍
Cache ID: 216::103

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

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