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MFSA2021-37 Firefox: Security Vulnerabilities fixed in Firefox 91.0.1 and Thunderbird 91.0.1 (CVE-2021-29991)

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MFSA2021-37 Firefox: Security Vulnerabilities fixed in Firefox 91.0.1 and Thunderbird 91.0.1 (CVE-2021-29991)

Severity
6
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:N)
Published
08/16/2021
Created
08/19/2021
Added
08/18/2021
Modified
11/26/2021

Description

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.

Solution(s)

  • mozilla-firefox-upgrade-91_0_1

References

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