CVE-2021-29964

Description

A locally-installed hostile program could send `WM_COPYDATA` messages that Firefox would process incorrectly, leading to an out-of-bounds read. *This bug only affects Firefox on Windows. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 78.11, Firefox < 89, and Firefox ESR < 78.11.

Category

7.1
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.32%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox
Affected: Mozilla Firefox ESR
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-26/ release notes vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-24/ release notes vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-23/ release notes vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1706501 permissions required vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-29964?
CVE-2021-29964 has been scored as a high severity vulnerability.
How to fix CVE-2021-29964?
To fix CVE-2021-29964, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-29964 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-29964 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-29964?
CVE-2021-29964 affects Mozilla Thunderbird, Mozilla Firefox, Mozilla Firefox ESR.
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