High severity · published Nov 3, 2021
CVE-2021-38493
Mozilla developers reported memory safety bugs present in Firefox 91 and Firefox ESR 78.13
8.8
CVSS
1.2%
EPSS
No
On KEV
Description
Mozilla developers reported memory safety bugs present in Firefox 91 and Firefox ESR 78.13. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 78.14, Thunderbird < 78.14, and Firefox < 92.
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)1.2% · higher than 69% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FI
Firefox · Mozilla
before 92.0 · source: NVD
FE
Firefox Esr · Mozilla
before 78.14 · source: NVD
TH
Thunderbird · Mozilla
before 78.14 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-38493
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-38493
Vendor Advisory
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1723391%2C1724101%2C1724107
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/mfsa2021-38/
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-39/
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-42/
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