Firefox EsrWeb browser · Mozilla
CVE-2022-38476
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA data race could occur in the <code>PK11_ChangePW</code> function, potentially leading to a use-after-free vulnerability. In Firefox, this lock protected the data when a user changed their master password. This vulnerability affects Firefox ESR < 102.2 and Thunderbird < 102.2.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceA data race in the PK11_ChangePW function in Firefox and Thunderbird allows potential concurrent access to password-protected data during master password changes. The lock meant to protect this sensitive operation is not properly synchronized, which could lead to a use-after-free vulnerability where memory is accessed after being freed.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Firefox EsrWeb browser
< 102.2< 102.2CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- High
- Privileges
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Check Firefox ESR versionIn Firefox, navigate to Help > About Firefox (or go to about:support in the address bar). Look for the version number displayed.Affected if The version displayed is less than 102.2 (for example, 102.1, 102.0, or earlier)
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Check Thunderbird versionIn Thunderbird, navigate to Help > About Thunderbird. Look for the version number displayed.Affected if The version displayed is less than 102.2 (for example, 102.1, 102.0, or earlier)
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Verify master password is in useIn Firefox or Thunderbird, go to Settings > Privacy & Security (or Options > Privacy & Security). Look for a 'Master Password' section and check if a master password has been set and is in use.Affected if A master password is enabled - the vulnerability occurs during master password changes, so this configuration must be present for the flaw to be exploitable
You are affected if you are running Firefox ESR or Thunderbird versions prior to 102.2 AND have a master password enabled, as the race condition occurs specifically during master password change operations.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped102.2
Update to Firefox ESR 102.2 or Thunderbird 102.2 or later to receive the patch that fixes the race condition in the PK11_ChangePW function.
Firefox ESR 102.2+ or Thunderbird 102.2+
- 1. Update Firefox ESR to version 102.2 or later
- 2. Update Thunderbird to version 102.2 or later
- 3. Restart the application after updating
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Firefox Esr
Scoped from the published advisory
- Consultation3.0 h
- Implementation6.0 h
- Testing5.0 h
- Review / QA3.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,752.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2022-38476 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2022-38476 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
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