Out-of-bounds Read in Mozilla Firefox

CVE-2020-6806

By carefully crafting promise resolutions, it was possible to cause an out-of-bounds read off the end of an array resized during script execution. This could have led to memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 68.6, Firefox < 74, Firefox < ESR68.6, and Firefox ESR < 68.6.

Vulnerability class: Buffer Overflow

EPSS: 0.025 (83.4th percentile) — read the EPSS interpretation.

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.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2020-6806?
CVE-2020-6806 is a high-severity vulnerability in Mozilla Firefox, classified under Out-of-bounds Read. CVSS score: 8.8/10. Published 2020-03-25.
How severe is CVE-2020-6806?
High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2020-6806 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.