CVE-2020-26974

Description

When flex-basis was used on a table wrapper, a StyleGenericFlexBasis object could have been incorrectly cast to the wrong type. This resulted in a heap user-after-free, memory corruption, and a potentially exploitable crash. This vulnerability affects Firefox < 84, Thunderbird < 78.6, and Firefox ESR < 78.6.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.29%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox ESR
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2020-54/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-56/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-55/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1681022 permissions required

Frequently Asked Questions

What is the severity of CVE-2020-26974?
CVE-2020-26974 has been scored as a high severity vulnerability.
How to fix CVE-2020-26974?
To fix CVE-2020-26974, 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-2020-26974 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-26974 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-2020-26974?
CVE-2020-26974 affects Mozilla Firefox, Mozilla Thunderbird, Mozilla Firefox ESR.
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