CVE-2026-109783
No known exploitation. EPSS puts it in the 5th percentile. Fixed in 153.5.
What to do
Find your product and version, then upgrade to the build on the right.
- Mozilla FirefoxFixed builds153.5Stated by: CVE record
- Mozilla ThunderbirdFixed builds153.5Stated by: CVE record
Versions as the sources state them. Full version matrix after sign-in
What it is
From the CVE record
Mitigation bypass in the File Handling component. This vulnerability was fixed in Firefox ESR 153.5 and Thunderbird 153.5.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.2% chance of exploitation activity in the next 30 days, which ranks it in the 5th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
4 events over 9 days, from the signal feeds we watch.
- OpenVAS check added
- Publishedrecord updated, record updated
Affected products
Sources
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