Buffer overflow in Mozilla Firefox

CVE-2020-26974

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.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.015 (73.9th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 74th percentile — 73.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2020-26974: held from 0.015 to 0.015.

EPSS over last 30 days · oldest: 0.015 · newest: 0.015 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-26974?
CVE-2020-26974 is a high-severity vulnerability in Mozilla Firefox, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2021-01-07.
How severe is CVE-2020-26974?
High severity. CVSS v3 base score is 8.8 out of 10.