SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2020-26959

During browser shutdown, reference decrementing could have occured on a previously freed object, resulting in a use-after-free, memory corruption, and a potentially exploitable crash.

HIGH 8.8EPSS 1.29%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.29%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

During browser shutdown, reference decrementing could have occured on a previously freed object, resulting in a use-after-free, memory corruption, and a potentially exploitable crash. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
1.29% probability · 69th percentile
CISA KEV
Not listed
Weakness
CWE-416
Affected
mozilla/firefox · mozilla/firefox esr · mozilla/thunderbird
Source
security@mozilla.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.