FirefoxWeb browser · Mozilla
CVE-2023-49061
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 · uneditedAn attacker could have performed HTML template injection via Reader Mode and exfiltrated user information. This vulnerability affects Firefox for iOS < 120.
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 · moderate confidenceFirefox for iOS Reader Mode feature contains an HTML template injection vulnerability that allows remote attackers to inject malicious HTML/script content through crafted web pages. When users view these pages in Reader Mode, the injected content can execute and exfiltrate sensitive user information such as cookies, session tokens, or other browser-stored data.
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
< 120.0CVSS 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
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/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 Firefox for iOS is installedCheck your device's installed applications for Mozilla Firefox for iOS. This vulnerability affects only the iOS version, not desktop Firefox.Affected if Firefox for iOS is present on the device
-
Identify the installed Firefox for iOS versionOpen the Firefox for iOS app, tap the menu (three horizontal lines), go to Settings, then scroll to the bottom where the version number is displayed. Alternatively, check the version in the iOS App Store app listing if installed from there.Affected if The displayed version number is lower than 120.0 (for example, 119.x, 118.x, etc.)
-
Determine if Reader Mode has been usedReview browsing history or manually test the Reader Mode feature by opening any webpage in Firefox for iOS and tapping the Reader Mode icon (usually a document icon in the address bar).Affected if Reader Mode feature has been accessed at least once
-
Assess potential exposure to untrusted contentConsider whether Reader Mode has been used on websites other than trusted, known-good sites. The vulnerability can be triggered by viewing crafted malicious pages in Reader Mode.Affected if Reader Mode was used on websites that could be controlled by untrusted parties
You are affected if Firefox for iOS version is below 120.0 AND you have used or may use Reader Mode on untrusted websites.
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 · scoped120.0
Upgrade Firefox for iOS to version 120 or later. Until then, avoid using Reader Mode on untrusted websites.
Firefox 120.0 for iOS
- Open the App Store on your iOS device
- Search for "Firefox" or locate it in your installed apps
- Tap "Update" to install Firefox version 120.0 or later
- Alternatively, enable automatic app updates in iOS Settings > App Store > Automatic Downloads to ensure future security updates are applied
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Firefox
Scoped from the published advisory
- Consultation2.0 h
- Implementation8.0 h
- Testing4.0 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 $4,768.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-49061 — 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-2023-49061 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