CVE-2021-23958

high

Published — · Modified —

CVSS v3

—

CVSS v2

—

VIR risk

8.0

Description

The browser could have been confused into transferring a screen sharing state into another tab, which would leak unintended information. This vulnerability affects Firefox < 85.

Predictions

Exploit likelihood

20%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2021-23958

vendor Authored 2026-05-27

Vendor advisory: arch — https://security.archlinux.org/ASA-202102-1

OS impact

OS	Version	Status	Fixed in
arch		fixed	`85.0-1`
debian	sid	fixed	`85.0-1`

References

https://security.archlinux.org/ASA-202102-1
https://security-tracker.debian.org/tracker/CVE-2021-23958

Verify integrity in audit chain (admin only). AS-IS.