Ubuntu update for firefox

1) HTTP response splitting

EUVDB-ID: #VU55935

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-29991

CWE-ID: CWE-113 - Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting')

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform HTTP splitting attacks.

The vulnerability exists due to the affected software incorrectly accepts a newline in a HTTP/3 header, interpretting it as two separate headers. A remote attacker can perform a header splitting attack against servers using HTTP/3.

Mitigation

Update the affected package firefox to the latest version.

Vulnerable software versions

Ubuntu: 18.04 - 21.04

firefox (Ubuntu package): before 91.0.1+build1-0ubuntu0.21.04.1

External links

http://ubuntu.com/security/notices/USN-5047-1

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.