CVE-2021-43535

Published: 8 December 2021

A use-after-free could have occured when an HTTP2 session object was released on a different thread, leading to memory corruption and a potentially exploitable crash. This vulnerability affects Firefox < 93, Thunderbird < 91.3, and Firefox ESR < 91.3.

Notes

Author	Note
tyhicks	mozjs contains a copy of the SpiderMonkey JavaScript engine

Priority

Cvss 3 Severity Score

8.8

Score breakdown

Status

Package	Release	Status
firefox Launchpad, Ubuntu, Debian	bionic	Not vulnerable (94.0+build3-0ubuntu0.18.04.1)
	focal	Not vulnerable (94.0+build3-0ubuntu0.20.04.1)
	hirsute	Not vulnerable (94.0+build3-0ubuntu0.21.04.1)
	impish	Not vulnerable (94.0+build3-0ubuntu0.21.10.1)
	jammy	Not vulnerable (94.0+build3-0ubuntu1)
	kinetic	Not vulnerable (94.0+build3-0ubuntu1)
	lunar	Not vulnerable (94.0+build3-0ubuntu1)
	trusty	Does not exist
	upstream	Needs triage
	xenial	Ignored (end of standard support, was needed)
thunderbird Launchpad, Ubuntu, Debian	bionic	Released (1:91.5.0+build1-0ubuntu0.18.04.1)
	focal	Released (1:91.5.0+build1-0ubuntu0.20.04.1)
	hirsute	Ignored (end of life)
	impish	Not vulnerable (1:91.3.1+build1-0ubuntu0.21.10.1)
	jammy	Not vulnerable (1:91.3.1+build1-0ubuntu1)
	kinetic	Not vulnerable (1:91.3.1+build1-0ubuntu1)
	lunar	Not vulnerable (1:91.3.1+build1-0ubuntu1)
	trusty	Does not exist
	upstream	Needs triage
	xenial	Ignored (end of standard support, was needed)

Severity score breakdown

Parameter	Value
Base score	8.8
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	Required
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References

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