SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2026-2781

Integer overflow in the Libraries component in NSS.

CRITICAL 9.8EPSS 0.36%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.36%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Integer overflow in the Libraries component in NSS. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, Thunderbird 140.8, and Firefox ESR 115.35.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.36% probability · 29th percentile
CISA KEV
Not listed
Weakness
CWE-190
Affected
mozilla/firefox · mozilla/thunderbird
Source
security@mozilla.org

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