Red Hat Security Advisory: firefox security update
Affects Red Hat firefoxSource GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 9.8 Critical : upgrade the Red Hat redhat/firefox package to 144.0 or 140.4 as a priority.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 43% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 144.0, 140.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 14 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Upgrade the Red Hat redhat/firefox package to 144.0 or 140.4.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Red Hatredhat/firefoxpkg:rpm/redhat/firefoxOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has released updated Firefox packages (version 140.4.0-3.el8_6) for Red Hat Enterprise Linux 8.6 variants that address these vulnerabilities. Users should apply these official updates promptly to remediate the security issues. For detailed update instructions, refer to Red Hat's advisory at https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the vendor-provided patches.
Description
A security update for Mozilla Firefox addresses multiple vulnerabilities including memory safety bugs, out-of-bounds read/write, use-after-free, cross-process information leaks, and improper handling of OBJECT tag attributes. These issues affect Firefox and Thunderbird products and have been fixed in Firefox ESR 140.4, Thunderbird ESR 140.4, Firefox 144, and Thunderbird 144. The update is rated as important by Red Hat Product Security and applies to Red Hat Enterprise Linux 8.6 variants.
References
- access.redhat.com/errata/RHSA-2025:21056 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403763 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403765 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403768 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403769 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403770 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403774 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403776 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2025/rhsa-2025_21056.json (opens in a new tab)