libtar libtar.c tar_close use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in libtar. The impacted element is the function tar_close of the file libtar.c. The manipulation results in use after free. This vulnerability is known as CVE-2021-33640. No exploit is available.

Detailsinfo

A vulnerability, which was classified as critical, was found in libtar (version unknown). Affected is the function tar_close of the file libtar.c. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

After tar_close(), libtar.c releases the memory pointed to by pointer t. After tar_close() is called in the list() function, it continues to use pointer t: free_longlink_longname(t->th_buf) . As a result, the released memory is used (use-after-free).

The weakness was published 12/19/2022. The advisory is shared for download at openeuler.org. This vulnerability is traded as CVE-2021-33640 since 05/28/2021. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 211208 (Fedora 37 : libtar (2022-88772d0a2d)), 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 (211208). Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.2
VulDB Meta Temp Score: 7.2

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

NVD Base Score: 9.8
NVD Vector: 🔍

CNA Base Score: 6.2
CNA Vector (openEuler): 🔍

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: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 211208
Nessus Name: Fedora 37 : libtar (2022-88772d0a2d)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

05/28/2021 🔍
12/19/2022 +570 days 🔍
12/19/2022 +0 days 🔍
04/02/2025 +835 days 🔍

Sourcesinfo

Advisory: FEDORA-2022-88772d0a2d
Status: Confirmed

CVE: CVE-2021-33640 (🔍)
GCVE (CVE): GCVE-0-2021-33640
GCVE (VulDB): GCVE-100-216300

Entryinfo

Created: 12/19/2022 20:29
Updated: 04/02/2025 21:00
Changes: 12/19/2022 20:29 (36), 01/15/2023 22:11 (1), 01/15/2023 22:22 (21), 11/16/2024 17:52 (17), 04/02/2025 21:00 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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