This page tracks the Debian fix status. The vulnerability itself is described on the main CVE page. View CVE-2026-16387 →

DEBIAN-CVE-2026-16387

Site isolation issue in the Networking component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 14...

Original description

The description as published by the source.

Site isolation issue in the Networking component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

Source: OSV.dev (Open Source Vulnerabilities) OSV

Affected packages

Debian:12 firefox-esr

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"140.13.0esr-1~deb12u1"}]}]

Debian:13 firefox-esr

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"140.13.0esr-1~deb13u1"}]}]

Debian:14 firefox-esr

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"140.13.0esr-1"}]}]

Debian:12 thunderbird

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:140.13.0esr-2~deb12u1"}]}]

Debian:13 thunderbird

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:140.13.0esr-2~deb13u1"}]}]

Debian:14 thunderbird

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:140.13.0esr-1"}]}]

References

advisory security-tracker.debian.org