XSS in Mozilla Firefox
CVE-2019-17016
When pasting a <style> tag from the clipboard into a rich text editor, the CSS sanitizer incorrectly rewrites a @namespace rule. This could allow for injection into certain types of websites resulting in data exfiltration. This vulnerability affects Firefox ESR < 68.4 and Firefox < 72.
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.020 (78.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
Affected products
- Mozilla Firefox — versions before 72
- Mozilla Firefox Esr — versions before 68.4
- Mozilla Firefox_esr
- Canonical Ubuntu_linux — versions 16.04, 18.04, 19.04
- Debian Debian_linux — versions 8.0, 9.0, 10.0
- Redhat Enterprise_linux_desktop — versions 6.0, 7.0
- Redhat Enterprise_linux_server — versions 6.0, 7.0
- Redhat Enterprise_linux_server_aus — versions 7.7
- Redhat Enterprise_linux_server_tus — versions 7.7
- Redhat Enterprise_linux_workstation — versions 6.0, 7.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security@mozilla.org (Permissions Required, x_refsource_MISC)
- security@mozilla.org (x_refsource_CONFIRM, Vendor Advisory)
- security@mozilla.org (x_refsource_CONFIRM, Vendor Advisory)
- security@mozilla.org (mailing-list, x_refsource_BUGTRAQ, Mailing List, Third Party Advisory)
- security@mozilla.org (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
- security@mozilla.org (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)
- security@mozilla.org (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
- security@mozilla.org (mailing-list, x_refsource_BUGTRAQ, Mailing List, Third Party Advisory)
- security@mozilla.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
- security@mozilla.org (x_refsource_REDHAT, vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2019-17016?
- CVE-2019-17016 is a medium-severity vulnerability in Mozilla Firefox, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2020-01-08.
- How severe is CVE-2019-17016?
- Medium severity. CVSS v3 base score is 6.1 out of 10.
- Is CVE-2019-17016 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.