CVE-2017-7767
The Mozilla Maintenance Service can be invoked by an unprivileged user to overwrite arbitrary files with junk data using the Mozilla Windows Updater, which runs with the Maintenance Service's privileged access.
Does this matter?
Lower severity and a low EPSS score (0.28%). Track it; it rarely justifies an emergency change on its own.
Description
The Mozilla Maintenance Service can be invoked by an unprivileged user to overwrite arbitrary files with junk data using the Mozilla Windows Updater, which runs with the Maintenance Service's privileged access. Note: This attack requires local system access and only affects Windows. Other operating systems are not affected. This vulnerability affects Firefox ESR < 52.2 and Firefox < 54.
- CVSS 3.0
- 5.5 MEDIUMCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 0.28% probability · 20th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-269
- Affected
- mozilla/firefox
- Source
- security@mozilla.org
EPSS 0.3% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.securityfocus.com/bid/99057Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1038689Third Party Advisory, VDB Entry
- https://bugzilla.mozilla.org/show_bug.cgi?id=1336964Issue Tracking, Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-15/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-16/Vendor Advisory
- http://www.securityfocus.com/bid/99057Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1038689Third Party Advisory, VDB Entry
- https://bugzilla.mozilla.org/show_bug.cgi?id=1336964Issue Tracking, Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-15/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2017-16/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.