CVE-2026-100793
JIT miscompilation in the JavaScript Engine component
02 Description
JIT miscompilation in the JavaScript Engine component
03 Exploitation and scoring
- Exploitation
- Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
- SSVC decision
- ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 0.26% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 18.8% of scored records. A rank, not a probability.
- NVD base score
- 6.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- NVD analysis status
- Analyzed. NVD last modified this record on 2026-10-19.
- Red Hat severity
- Important. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2026-09-29 12:36Z29 DAYS AGO
- Last updated
- 2026-10-01 14:52Z27 DAYS AGO
- Reserved
- 2026-09-26
- Assigning CNA
- mozilla
- Record state
- PUBLISHED
- Severity
- Medium (CVSS 6.5)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- Weaknesses
- CWE-843Access of Resource Using Incompatible Type ('Type Confusion')Base
- Data version
- 5.2
- Document digest
- 35cf2fce07b5dacb5d3650f1960fff1d43680d7a693fe1723172defb1874b515
05 Affected products
06 References
- bugzilla.mozilla.orghttps://bugzilla.mozilla.org/show_bug.cgi?id=2073268
- www.mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-101/
- www.mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-97/
07 Fixed in
Ubuntu 18.04 LTS
- mozjs38 No fix yet
- mozjs52 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 20.04 LTS
- mozjs52 No fix yet
- mozjs68 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 22.04 LTS
- mozjs102 No fix yet
- mozjs78 No fix yet
- mozjs91 No fix yet
- thunderbird No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 24.04 LTS
- mozjs102 No fix yet
- mozjs115 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.