CVE-2021-38114

Service interruption via unchecked VLC initialization

Published Aug 4, 2021 · Updated Aug 4, 2024

Unchecked return handling in FFmpeg 4.4 allows context-dependent attackers to interrupt service through crafted DNxHD video data. The DNxHD decoder ignores failures from three init_vlc calls for AC, DC, and run tables, then proceeds as though table initialization succeeded. Exploitation requires a user or application to process attacker-controlled DNxHD content; published sources do not specify the resulting failure mode.

CVSS severity5.5
Medium
EPSS probability1.03%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Unchecked return handling in FFmpeg 4.4 allows context-dependent attackers to interrupt service through crafted DNxHD video data. The DNxHD decoder ignores failures from three init_vlc calls for AC, DC, and run tables, then proceeds as though table initialization succeeded. Exploitation requires a user or application to process attacker-controlled DNxHD content; published sources do not specify the resulting failure mode.

The record

CVE
CVE-2021-38114
Published
Aug 4, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-252, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 4, 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 vectorlocal
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
5.5NIST NVDCVSS:3.1/AV:L/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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-252Unchecked Return Value
T1204.002Malicious File

Public exploit references

No public exploit references are available in this record.

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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