CVE-2020-20450Network attack vector

Process crash via null MXF codec UID

Published May 25, 2021 · Updated Aug 4, 2024

Null pointer dereference in FFmpeg 4.2 allows remote attackers to crash a media-processing service through crafted multimedia input. The MXF muxer sets codec_ul to NULL for an unsupported video profile, then writes a delayed header after a following audio packet and dereferences the missing UID. The service must accept attacker-controlled media for MXF muxing; the published impact is a process crash, not data disclosure or modification.

CVSS severity7.5
High
EPSS probability1.08%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Null pointer dereference in FFmpeg 4.2 allows remote attackers to crash a media-processing service through crafted multimedia input. The MXF muxer sets codec_ul to NULL for an unsupported video profile, then writes a delayed header after a following audio packet and dereferences the missing UID. The service must accept attacker-controlled media for MXF muxing; the published impact is a process crash, not data disclosure or modification.

The record

CVE
CVE-2020-20450
Published
May 25, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-476, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 25, 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

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P

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 exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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