A vulnerability exists during authorization prompting for FTP transaction where successive modal prompts are displayed and cannot be immedi…

published 2019-04-26 7y ago modified 2026-06-17 4mo ago also EUVD-2019-19168

cvss: 7.5; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 65%
public exploits: 0; none known

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.

Patch / fix

fixed in 1 distros 3

Mozilla Firefox 66

ubuntu opensuse arch linux

firefox Ubuntu 14.04 LTS 66.0.1+build1-0ubuntu0.14.04.1
firefox Ubuntu 16.04 LTS 66.0+build3-0ubuntu0.16.04.2
firefox Ubuntu 18.04 LTS 66.0+build3-0ubuntu0.18.04.1

ubuntu advisories UBUNTU-CVE-2019-9806

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

firefox-esr openSUSE Tumbleweed 128.5.1-1.1
MozillaFirefox openSUSE Tumbleweed 92.0-1.2

opensuse advisories openSUSE-SU-2024:14572-1 openSUSE-SU-2024:10600-1

firefox Arch Linux 66.0-1

arch linux advisories AVG-925

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Exploit prediction

1.08% chance of exploitation in the next 30 days, higher than 65% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.0	7.5	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

Mozilla Firefox

Classification

Weakness

CWE-399 Resource Management Errors

References

mozilla.org /security/advisories/mfsa2019-07/
vendor-advisory
bugzilla.mozilla.org /show_bug.cgi?id=1525267
issue-tracking, permissions-required, vendor-advisory

Sources

CVE List CVE-2019-9806
NVD CVE-2019-9806

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