HTTP Request Smuggling Affecting firefox package, versions <91.0.1+build1-0ubuntu0.21.04.1


Severity

Recommended
medium

Based on Ubuntu security rating.

Threat Intelligence

EPSS
0.16% (53rd percentile)

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  • Snyk IDSNYK-UBUNTU2104-FIREFOX-1567419
  • published19 Aug 2021
  • disclosed3 Nov 2021

Introduced: 19 Aug 2021

CVE-2021-29991  (opens in a new tab)
CWE-444  (opens in a new tab)

How to fix?

Upgrade Ubuntu:21.04 firefox to version 91.0.1+build1-0ubuntu0.21.04.1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream firefox package and not the firefox package as distributed by Ubuntu. See How to fix? for Ubuntu:21.04 relevant fixed versions and status.

Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers. This allowed for a header splitting attack against servers using HTTP/3. This vulnerability affects Firefox < 91.0.1 and Thunderbird < 91.0.1.

CVSS Scores

version 3.1