CVE-2021-29959Public exploitNetwork attack vector

Camera reactivation via combined temporary permission tracking

Published Jun 24, 2021 · Updated Aug 3, 2024

Incorrect authorization in Mozilla Firefox before 89 allows remote attackers to resume camera capture without a new permission prompt. MediaManager retained temporary camera permission at the combined capture-request level and cleared it only after all tracks ended, rather than when the camera track stopped. Exploitation requires the user to have granted camera and microphone access and the site to keep the microphone recording while it restarts the camera.

CVSS severity4.3
Medium
EPSS probability0.84%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect authorization in Mozilla Firefox before 89 allows remote attackers to resume camera capture without a new permission prompt. MediaManager retained temporary camera permission at the combined capture-request level and cleared it only after all tracks ended, rather than when the camera track stopped. Exploitation requires the user to have granted camera and microphone access and the site to keep the microphone recording while it restarts the camera.

The record

CVE
CVE-2021-29959
Published
Jun 24, 2021
Updated
Aug 3, 2024
Vendor
Mozilla
Product
Firefox
Classifications
CWE-863, T1125
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 24, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

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

  1. Affected versionversion=unspecified <89

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mozilla · Firefoxversion=unspecified <89

Published CVSS scores

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

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

CWE-863Incorrect Authorization
T1125Video Capture

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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