CVE-2020-21605Public exploitNetwork attack vector

Decoder crash via crafted HEVC file

Published Sep 16, 2021 · Updated Aug 4, 2024

A segmentation fault in libde265 1.0.4 allows attackers to crash a target application by supplying a crafted HEVC file. During sample adaptive offset postprocessing, apply_sao_internal dereferences an invalid address while decoding malformed stream state. The target must decode the file, and the demonstrated consequence is process termination rather than code execution.

CVSS severity6.5
Medium
EPSS probability1.01%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A segmentation fault in libde265 1.0.4 allows attackers to crash a target application by supplying a crafted HEVC file. During sample adaptive offset postprocessing, apply_sao_internal dereferences an invalid address while decoding malformed stream state. The target must decode the file, and the demonstrated consequence is process termination rather than code execution.

The record

CVE
CVE-2020-21605
Published
Sep 16, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 16, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1204.002Malicious File

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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