EPSS
Percentile
53.0%
firefox:sid is vulnerable to header splitting attack. Firefox incorrectly accepted a newline in a HTTP/3 header, interpreting it as two separate headers, allowing a header splitting attack against servers using HTTP/3.
bugzilla.mozilla.org/show_bug.cgi?id=1724896
security-tracker.debian.org/tracker/CVE-2021-29991
www.mozilla.org/security/advisories/mfsa2021-37/