How severe is CVE-2020-21596?

CVE-2020-21596 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-21596 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-21596?

CVE-2020-21596 primarily affects Struktur Libde265. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-21596?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-21596 published?

CVE-2020-21596 was published on 2021-09-16 and last updated on 2026-06-17.

CVE-2020-21596

CVE-2020-21596 is a medium-severity vulnerability in Struktur Libde265 with a CVSS 3.x base score of 6.5. 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-120.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Struktur Libde265
Published: 2021-09-16
Last modified: 2026-06-17

Description

libde265 v1.0.4 contains a global buffer overflow in the decode_CABAC_bit function, which can be exploited via a crafted a file.

Frequently asked questions

What is CVE-2020-21596?: libde265 v1.0.4 contains a global buffer overflow in the decode_CABAC_bit function, which can be exploited via a crafted a file.
How severe is CVE-2020-21596?: CVE-2020-21596 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-21596 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-21596?: CVE-2020-21596 primarily affects Struktur Libde265. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-21596?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-21596 published?: CVE-2020-21596 was published on 2021-09-16 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:struktur:libde265:1.0.4:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

More vulnerabilities in Struktur Libde265

CVE-2022-1253 — Critical (CVSS 9.8): Heap-based Buffer Overflow in GitHub repository strukturag/libde265 prior to and including 1.0.8. The fix is…
CVE-2023-49468 — High (CVSS 8.8): Libde265 v1.0.14 was discovered to contain a global buffer overflow vulnerability in the read_coding_unit function at…
CVE-2023-49467 — High (CVSS 8.8): Libde265 v1.0.14 was discovered to contain a heap-buffer-overflow vulnerability in the…
CVE-2023-49465 — High (CVSS 8.8): Libde265 v1.0.14 was discovered to contain a heap-buffer-overflow vulnerability in the…
CVE-2023-27103 — High (CVSS 8.8): Libde265 v1.0.11 was discovered to contain a heap buffer overflow via the function derive_collocated_motion_vectors at…
CVE-2020-21598 — High (CVSS 8.8): libde265 v1.0.4 contains a heap buffer overflow in the ff_hevc_put_unweighted_pred_8_sse function, which can be…

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