High severity · published Aug 17, 2021
CVE-2021-29984
Instruction reordering resulted in a sequence of instructions that would cause an object to be incorrectly considered during garbage collection
8.8
CVSS
1.4%
EPSS
No
On KEV
Description
Instruction reordering resulted in a sequence of instructions that would cause an object to be incorrectly considered during garbage collection. This led to memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.13, Thunderbird < 91, Firefox ESR < 78.13, and Firefox < 91.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.4% · higher than 72% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FI
Firefox · Mozilla
before 91.0 · source: NVD
FE
Firefox Esr · Mozilla
before 78.13.0 · source: NVD
TH
Thunderbird · Mozilla
before 78.13.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-29984
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-29984
Exploit
https://bugzilla.mozilla.org/show_bug.cgi?id=1720031
Third Party Advisory
https://security.gentoo.org/glsa/202202-03
Third Party Advisory
https://security.gentoo.org/glsa/202208-14
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-33/
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-34/
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-35/
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