XSS in Mozilla Firefox
CVE-2018-5143
URLs using "javascript:" have the protocol removed when pasted into the addressbar to protect users from cross-site scripting (XSS) attacks, but if a tab character is embedded in the "javascript:" URL the protocol is not removed and the script will execute. This could allow users to be socially engineered to run an XSS attack against themselves. This vulnerability affects Firefox < 59.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.009 (59.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 59.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000
Affected products
- Mozilla Firefox — versions unspecified
- Canonical Ubuntu Linux — versions 14.04, 16.04, 17.10
Weakness classification (CWE)
References
- bugzilla.mozilla.org/show_bug.cgi (Issue Tracking, Vendor Advisory)
- www.securityfocus.com/bid/103386 (VDB Entry, Third Party Advisory, vdb-entry)
- www.securitytracker.com/id/1040514 (VDB Entry, Third Party Advisory, vdb-entry)
- usn.ubuntu.com/3596-1/ (vendor-advisory, Third Party Advisory)
- www.mozilla.org/security/advisories/mfsa2018-06/ (Vendor Advisory)
Frequently asked questions
- What is CVE-2018-5143?
- CVE-2018-5143 is a medium-severity vulnerability in Mozilla Firefox, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2018-06-11.
- How severe is CVE-2018-5143?
- Medium severity. CVSS v3 base score is 6.1 out of 10.