What is CVE-2017-7797?

CVE-2017-7797 is a high-severity vulnerability in Mozilla Firefox, classified under Origin Validation Error. CVSS score: 7.5/10. Published 2018-06-11.

How severe is CVE-2017-7797?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Mozilla Firefox

CVE-2017-7797

Response header name interning does not have same-origin protections and these headers are stored in a global registry. This allows stored header names to be available cross-origin. This vulnerability affects Firefox < 55.

Published 2018-06-11 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.008 (54.9th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 54.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Mozilla Firefox — versions unspecified

Weakness classification (CWE)

CWE-346 — Origin Validation Error

References

bugzilla.mozilla.org/show_bug.cgi (Exploit, Patch, Issue Tracking)
www.mozilla.org/security/advisories/mfsa2017-18/ (Vendor Advisory)
www.securitytracker.com/id/1039124 (VDB Entry, Third Party Advisory, vdb-entry)

Frequently asked questions

What is CVE-2017-7797?: CVE-2017-7797 is a high-severity vulnerability in Mozilla Firefox, classified under Origin Validation Error. CVSS score: 7.5/10. Published 2018-06-11.
How severe is CVE-2017-7797?: High severity. CVSS v3 base score is 7.5 out of 10.