VulnerabilityModified
CVE-2019-17023
This vulnerability affects Firefox < 72.
MEDIUM 6.5EPSS 1.34%
Does this matter?
Lower severity and a low EPSS score (1.34%). Track it; it rarely justifies an emergency change on its own.
Description
After a HelloRetryRequest has been sent, the client may negotiate a lower protocol that TLS 1.3, resulting in an invalid state transition in the TLS State Machine. If the client gets into this state, incoming Application Data records will be ignored. This vulnerability affects Firefox < 72.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
- EPSS
- 1.34% probability · 71th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-287
- Affected
- mozilla/firefox · canonical/ubuntu linux · debian/debian linux
- Source
- security@mozilla.org
EPSS 1.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1590001Issue Tracking, Permissions Required
- https://usn.ubuntu.com/4234-1/Third Party Advisory
- https://usn.ubuntu.com/4397-1/Third Party Advisory
- https://www.debian.org/security/2020/dsa-4726Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-01/Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1590001Issue Tracking, Permissions Required
- https://usn.ubuntu.com/4234-1/Third Party Advisory
- https://usn.ubuntu.com/4397-1/Third Party Advisory
- https://www.debian.org/security/2020/dsa-4726Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-01/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.