SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2026-2762

Integer overflow in the JavaScript: Standard Library component.

CRITICAL 9.8EPSS 0.54%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.54%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Integer overflow in the JavaScript: Standard Library component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

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
0.54% probability · 44th percentile
CISA KEV
Not listed
Weakness
CWE-190
Affected
mozilla/firefox · mozilla/thunderbird
Source
security@mozilla.org

References

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