CVE-2017-7761

Name: CVE-2017-7761
Creator: NVD / NIST
Published: 2018-06-11T21:29:08.297+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

UnknownEPSS 0.31%

Last modified Jun 17, 2026

CVE-2017-7761 is a vulnerability of currently unknown severity. The Mozilla Maintenance Service "helper.exe" application creates a temporary directory writable by non-privileged users. When this is combined with creation of a junction (a form of symbolic link), protected files in the target directory of the junction can be deleted by the Mozilla Maintenance Service, which has privileged access. EPSS estimates a 0.31% chance of exploitation in the next 30 days.

Description

The Mozilla Maintenance Service "helper.exe" application creates a temporary directory writable by non-privileged users. When this is combined with creation of a junction (a form of symbolic link), protected files in the target directory of the junction can be deleted by the Mozilla Maintenance Service, which has 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.

Metrics

EPSS Probability

0.31%

22.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-276

Affected Software

Vendor	Product	Versions
Mozilla	Firefox	< 52.2.0
Mozilla	Firefox	< 54.0

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=1215648Issue Tracking, Vendor Advisory
https://sourceforge.net/p/nsis/bugs/1125/Issue Tracking, Third Party 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=1215648Issue Tracking, Vendor Advisory
https://sourceforge.net/p/nsis/bugs/1125/Issue Tracking, Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2017-15/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2017-16/Vendor Advisory

Timeline

Published: Jun 11, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2017-7761?

How severe is CVE-2017-7761?

Severity scoring for CVE-2017-7761 is pending analysis. The EPSS model estimates a 0.31% probability of exploitation in the next 30 days.

How do I fix CVE-2017-7761?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2017-7761?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST