Off-by-one out of bounds read in MIME header parser for forwarding (Mozilla Thunderbird)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.47 % · percentile 41 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- mozilla
- NVD status
- Analyzed
Description
The code to parse MIME headers for display when forwarding a message (if the setting to view all headers was enabled) had an off-by-one error, allowing a single byte to be read from the memory after the buffer for the headers, and potentially crashing Thunderbird. This vulnerability was fixed in Thunderbird 153 and Thunderbird 140.13.
Weaknesses (CWE)
- CWE-193 — Off-by-one Error
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N | CISA-ADP |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N | NVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary) |
European references
- ENISA EUVD · EUVD-2026-47773
- GCVE · GCVE-0-2026-14899
CERT-FR advisories
- CERTFR-2026-AVI-0913 — Multiples vulnérabilités dans Mozilla Thunderbird · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*< 140.13.0
Affected products
| Product | Versions |
|---|---|
| Mozilla · Thunderbird | unaffected 140.13 ≤ 140.* ; unaffected 153 ≤ * |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |