FirefoxWeb browser · Mozilla
CVE-2023-29545
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 · uneditedSimilar to CVE-2023-28163, this time when choosing 'Save Link As', suggested filenames containing environment variable names would have resolved those in the context of the current user. *This bug only affects Firefox and Thunderbird on Windows. Other versions of Firefox and Thunderbird are unaffected.* This vulnerability affects Firefox < 112, Firefox ESR < 102.10, and Thunderbird < 102.10.
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 confidenceWhen using 'Save Link As' in Firefox or Thunderbird on Windows, suggested filenames containing environment variable syntax (e.g., %TEMP%, %USERPROFILE%) would be resolved to their actual values in the current user's context, potentially exposing sensitive environment variable information to remote servers or intermediaries.
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
FirefoxWeb browser
< 112.0
Firefox EsrWeb browser
< 102.10< 102.10CVSS 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
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
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.
-
Confirm Windows operating systemRun 'systeminfo | findstr /B /C:"OS Name"' or check system properties to verify the OSAffected if Not running Windows - the vulnerability only affects Windows systems
-
Check Firefox versionNavigate to Firefox menu > Help > About Firefox, or run 'firefox --version' in command promptAffected if Firefox version is below 112.0, or below 102.10 if using ESR branch
-
Check Thunderbird versionNavigate to Thunderbird menu > Help > About Thunderbird, or run 'thunderbird --version' in command promptAffected if Thunderbird version is below 102.10
User is affected if running Windows with an unpatched Firefox (below 112.0 or below 102.10 ESR) or unpatched Thunderbird (below 102.10), and the Save Link As feature has been used with remote content.
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 · scoped102.10112.0
Upgrade to Firefox 112 or later, Firefox ESR 102.10 or later, or Thunderbird 102.10 or later. This is a client-side patch; no configuration changes needed.
Firefox 112.0, Firefox ESR 102.10, or Thunderbird 102.10
- Back up Firefox/Thunderbird data (bookmarks, passwords, extensions) using Firefox Sync or manual backup
- Open Firefox/Thunderbird and navigate to Help > About to trigger automatic update, or download the fixed version from https://www.mozilla.org/
- Install the update (Firefox 112.0, Firefox ESR 102.10, or Thunderbird 102.10)
- Restart the application to complete the installation
- Verify the version by checking Help > About to confirm the update was successful
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Firefox
Scoped from the published advisory
- Consultation1.0 h
- Implementation1.0 h
- Testing1.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,200.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-29545 — 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-2023-29545 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
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data