CVE-2026-3846: Mozilla Firefox · CWE-346
Affects Mozilla FirefoxSource CVE Database V5
Not known to be exploited · CVSS 6.5 Medium · patch available : update Mozilla Firefox when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% 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:N/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 10 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by 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
| Product | Affected | Fixed in |
|---|---|---|
| Mozilla Firefox | Affected
| Fixed in
|
AI-suggested
A security update fixing this vulnerability is available in Mozilla Firefox version 148.0.2. Users and administrators should apply this official fix promptly to mitigate the risk. Since the vendor advisory confirms the issue is fixed, no additional mitigation steps are required beyond updating to the patched version.
Description
Same-origin policy bypass in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 148.0.2.