Skip to main content
VulnerabilityPublished Updated

CVE-2026-8952: Mozilla Firefox · Improper Privilege Management

Affects Mozilla FirefoxSource CVE Database V5

0
Compare

Not known to be exploited · CVSS 8.8 High · patch available : patch Mozilla Firefox soon.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score
8.8High
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.3% chance of exploitation in 30 days – higher than 31% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 19 May 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponized: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

What to do

Affected software

ProductAffectedFixed in
Mozilla FirefoxAffected
  • <151
Fixed in
  • 151

AI-suggested

Mozilla has fixed this vulnerability in Firefox 151 and Thunderbird 151. Users and administrators should update to these versions or later to remediate the issue. Since this is not a cloud service, patching the client software is required. No additional mitigation steps are indicated by the vendor advisory.

Description

CVE-2026-8952 is a privilege escalation vulnerability in the Application Update component of Mozilla Firefox and Thunderbird. This vulnerability has been fixed in Firefox 151 and Thunderbird 151. The issue was reported by Tomoya Nakanishi and is classified with moderate impact by Mozilla. The vulnerability allows an attacker to escalate privileges within the affected application. Mozilla has released security advisories confirming the fix in the specified versions. No known exploits in the wild have been reported. The CVSS score for this vulnerability is 8.8, indicating a high severity level overall, but Mozilla rates the impact of this specific issue as moderate.

References

Community reviews

Loading reviews…