CVE-2023-29340

User-assisted arbitrary code execution

Published May 9, 2023 · Updated Jul 10, 2025

Remote code execution in Microsoft AV1 Video Extension before 1.1.60961.0 allows context-dependent attackers to run code through malicious AV1 content. Microsoft has not published the affected decoder routine or the operation it performs incorrectly while processing untrusted AV1 data. Exploitation requires the extension to be installed and a user to open or follow attacker-supplied content, after which code runs on the affected Windows host.

CVSS severity7.8
High
EPSS probability0.67%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Remote code execution in Microsoft AV1 Video Extension before 1.1.60961.0 allows context-dependent attackers to run code through malicious AV1 content. Microsoft has not published the affected decoder routine or the operation it performs incorrectly while processing untrusted AV1 data. Exploitation requires the extension to be installed and a user to open or follow attacker-supplied content, after which code runs on the affected Windows host.

The record

CVE
CVE-2023-29340
Published
May 9, 2023
Updated
Jul 10, 2025
Vendor
Microsoft
Product
AV1 Video Extension
Classifications
T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 9, 2023CVE publishedPublication date reported by the CVE source.
  2. Jul 10, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.1.0 <1.1.60961.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Microsoft · AV1 Video Extensionversion=1.1.0 <1.1.60961.0

Published CVSS scores

6.8Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
7.8Microsoft CorporationCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1204.002User Execution: Malicious File

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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