CVE-2019-9806

critical

Published — · Modified —

CVSS v3

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CVSS v2

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VIR risk

9.5

Description

A vulnerability exists during authorization prompting for FTP transaction where successive modal prompts are displayed and cannot be immediately dismissed. This allows for a denial of service (DOS) attack. This vulnerability affects Firefox < 66.

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-2019-9806

vendor Authored 2026-05-27

Vendor advisory: arch — https://security.archlinux.org/ASA-201903-11

OS impact

OS	Version	Status	Fixed in
arch		fixed	`66.0-1`
debian	sid	fixed	`66.0-1`

References

https://security.archlinux.org/ASA-201903-11
https://security-tracker.debian.org/tracker/CVE-2019-9806

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