Mozilla Firefox für Android: Schwachstelle ermöglicht Offenlegung von Informationen
WID-SEC-2026-2655 · first 05.08.2026 · updated 05.08.2026 · CVSS 6,5
What it is about
Firefox ist ein Open Source Web Browser. Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Mozilla Firefox für Android ausnutzen, um Informationen offenzulegen.
Under what conditions?
Over the network and without logging in. This is the most dangerous combination: attackers can scan reachable devices automatically.
What can happen in the worst case
An attacker could use the vulnerability to
- Informationen offenzulegen
Am I affected?
Affected according to the BSI:
- Mozilla Firefox <153.0.3
The installed version is usually shown under “Help → About” or in the device’s admin interface.
What helps?
Update to at least:
- Mozilla Firefox 153.0.3
Is the vulnerability already being exploited?
None of the CVEs is in the CISA catalogue of exploited vulnerabilities. That does not mean there are no attacks, only that none are documented.
Information and sources
- Original BSI advisory (WID)
- Mozilla Security Advisory mfsa2026-73 vom 2026-08-04 www.mozilla.org
- GitHub Security Advisory GHSA-v5x7-vhwf-5v44 vom 2026-08-04 github.com
CVE: CVE-2026-18809
Source: BSI warning and information service (CERT-Bund); CISA. The assessment of the conditions is my reading of the BSI text; the external pages are in their original language.