CVE-2026-96869: mozilla firefox
CVSS: 4.3v3.1MediumAnalyzed
AliasesUBUNTU-CVE-2026-96869DEBIAN-CVE-2026-96869
Published 29-09-2026Last modified 30-09-2026
Vulnerability summary
CVE-2026-96869 is a medium (CVSS 4.3) vulnerability in mozilla firefox. EPSS estimates a 0.20% chance of exploitation in the next 30 days, higher than 8.7% of scored vulnerabilities.
CVSS score
4.3/10
010
Medium · v3.1 (CVE.org)EPSS score
0.20%
0%100%
Low · Change unavailableKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 10 · Related 8Timeline
- 29-09-2026PublishedVulnerability first disclosed.
- 30-09-2026Last modifiedVulnerability information updated.
Description
Information disclosure in the Networking component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
CVSS metrics
4 scores · 4 sources · 1 versionMedium 4.3Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:NSourcesAll 4 agree
- OSV · UbuntuEcosystem advisory · calculated4.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
- OSV · DebianEcosystem advisory · calculated4.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
- NVDNIST4.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
EPSS trend
Probability
0.20%
Chance of exploitation in the next 30 days
Percentile
9%
Versus all other CVEs
30-day change
Change unavailable
Change unavailable
30-09-202619-10-2026
EPSS score0.20%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu8 products
- mozjs102All versions (No fix recorded)
- mozjs115All versions (No fix recorded)
- mozjs38All versions (No fix recorded)
- mozjs52All versions (No fix recorded)
- mozjs68All versions (No fix recorded)
Debian2 products
- firefox-esr< 153.4.0esr-1~deb12u1 | < 153.4.0esr-1~deb13u1 | < 153.4.0esr-1
- thunderbird< 1:140.17.0esr-1~deb12u1 | < 1:140.17.0esr-1~deb13u1 | < 1:153.4.0esr-1
Mozilla2 products
- firefox< 140.17.0 | ≥ 141.0, < 153.4.0 | ≥ 154.0.0, < 157.0.0
- thunderbird< 140.17.0 | ≥ 141.0, < 153.4.0 | ≥ 154.0, < 157.0
3 vendors · 12 products
References
12 links- www.mozilla.org/security/advisories/mfsa2026-101/Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-102/Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-103/Vendor Advisory