CVE-2022-26386: mozilla firefox_esr Insecure Temporary File
Vulnerability summary
CVE-2022-26386 is a medium (CVSS 6.5) Insecure Temporary File vulnerability in mozilla firefox_esr. EPSS estimates a 0.69% chance of exploitation in the next 30 days, higher than 51.9% of scored vulnerabilities. 1 public exploit is recorded.
Advisory lineage
Upstream 0 · Downstream 25 · Related 9Timeline
- 22-12-2022PublishedVulnerability first disclosed.
- 15-04-2025Last modifiedVulnerability information updated.
Description
Previously Firefox for macOS and Linux would download temporary files to a user-specific directory in <code>/tmp</code>, but this behavior was changed to download them to <code>/tmp</code> where they could be affected by other local users. This behavior was reverted to the original, user-specific directory. <br>*This bug only affects Firefox for macOS and Linux. Other operating systems are unaffected.*. This vulnerability affects Firefox ESR < 91.7 and Thunderbird < 91.7.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- OSV · DebianEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- NVDNIST6.5MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS trend
Probability
0.69%
Chance of exploitation in the next 30 days
Percentile
52%
Versus all other CVEs
30-day change
+0.01 pp
From 0.68% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundExploit Reference (bugzilla.mozilla.org)
Maturity: unknown
Weaknesses
CWE · root causeAffected systems
Debian2 products
- firefox-esr< 91.7.0esr-1
- thunderbird< 1:91.7.0-1
Mozilla2 products
- firefox_esr≥ unspecified, < 91.7 | < 91.7
- thunderbird≥ unspecified, < 91.7 | < 91.7
Ubuntu1 product
- thunderbird< 1:91.7.0+build2-0ubuntu0.18.04.1 | < 1:91.7.0+build2-0ubuntu0.20.04.1 | < 1:91.7.0+build2-0ubuntu1
3 vendors · 5 products
References
8 links- www.mozilla.org/security/advisories/mfsa2022-12/Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2022-11/Vendor Advisory
