How severe is CVE-2021-33645?

CVE-2021-33645 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-33645 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33645?

CVE-2021-33645 primarily affects Feep Libtar. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-33645?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-33645 published?

CVE-2021-33645 was published on 2022-08-10 and last updated on 2026-06-17.

CVE-2021-33645

CVE-2021-33645 is a high-severity vulnerability in Feep Libtar with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-401.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-401
Affected product: Feep Libtar
Published: 2022-08-10
Last modified: 2026-06-17

Description

The th_read() function doesn’t free a variable t->th_buf.gnu_longlink after allocating memory, which may cause a memory leak.

Frequently asked questions

What is CVE-2021-33645?: The th_read() function doesn’t free a variable t->th_buf.gnu_longlink after allocating memory, which may cause a memory leak.
How severe is CVE-2021-33645?: CVE-2021-33645 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-33645 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33645?: CVE-2021-33645 primarily affects Feep Libtar. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-33645?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-33645 published?: CVE-2021-33645 was published on 2022-08-10 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:feep:libtar:*:*:*:*:*:*:*:*
cpe:2.3:o:openatom:openeuler:20.03:sp1:*:*:lts:*:*:*
cpe:2.3:o:openatom:openeuler:20.03:sp3:*:*:lts:*:*:*
cpe:2.3:o:openatom:openeuler:22.03:*:*:*:lts:*:*:*
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*

More vulnerabilities in Feep Libtar

CVE-2021-33643 — Critical (CVSS 9.1): An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of…
CVE-2021-33644 — High (CVSS 8.1): An attacker who submits a crafted tar file with size in header struct being 0 may be able to trigger an calling of…
CVE-2021-33646 — High (CVSS 7.5): The th_read() function doesn’t free a variable t->th_buf.gnu_longname after allocating memory, which may cause a…
CVE-2013-4397 — Medium (CVSS 6.8): Multiple integer overflows in the th_read function in lib/block.c in libtar before 1.2.20 allow remote attackers to…
CVE-2013-4420 — Medium (CVSS 5.8): Multiple directory traversal vulnerabilities in the (1) tar_extract_glob and (2) tar_extract_all functions in libtar…

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CVE-2023-33718 — High (CVSS 8.8): mp4v2 v2.1.3 was discovered to contain a memory leak via MP4File::ReadString() at mp4file_io.cpp
CVE-2021-40633 — High (CVSS 8.8): A memory leak (out-of-memory) in gif2rgb in util/gif2rgb.c in giflib 5.1.4 allows remote attackers trigger an out of…
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