How severe is CVE-2020-21598?

CVE-2020-21598 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-21598 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-21598?

CVE-2020-21598 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-2020-21598?

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-2020-21598 published?

CVE-2020-21598 was published on 2021-09-16 and last updated on 2026-06-17.

CVE-2020-21598

CVE-2020-21598 is a high-severity vulnerability in Struktur Libde265 with a CVSS 3.x base score of 8.8. 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-787.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.8
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Struktur Libde265
Published: 2021-09-16
Last modified: 2026-06-17

Description

libde265 v1.0.4 contains a heap buffer overflow in the ff_hevc_put_unweighted_pred_8_sse function, which can be exploited via a crafted a file.

Frequently asked questions

What is CVE-2020-21598?: libde265 v1.0.4 contains a heap buffer overflow in the ff_hevc_put_unweighted_pred_8_sse function, which can be exploited via a crafted a file.
How severe is CVE-2020-21598?: CVE-2020-21598 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-21598 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-21598?: CVE-2020-21598 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-2020-21598?: 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-2020-21598 published?: CVE-2020-21598 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-2023-43887 — High (CVSS 8.1): Libde265 v1.0.12 was discovered to contain multiple buffer overflows via the num_tile_columns and num_tile_row…

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