Skip to content
Fencer Vulns
medium 6.5

CVE-2019-17023 json

After a HelloRetryRequest has been sent, the client may negotiate a lower protocol that TLS 1.3, resulting in an invalid state transition i…

published 2020-01-08 6 y ago modified 2026-06-17 4 mo ago also EUVD-2019-7497

cvss
6.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.3%
EPSS 1.3% chance of exploitation in 30 days, percentile 71%
public exploits
0
none known

Summary

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.

Patch / fix

  • mozilla firefox 72.0
  • nss Debian 14, Debian 13, Debian 12 2:3.49-1

debian advisories DEBIAN-CVE-2019-17023

  • nss Ubuntu 18.04 LTS 2:3.35-2ubuntu2.8
  • firefox Ubuntu 16.04 LTS 72.0.1+build1-0ubuntu0.16.04.1
  • firefox Ubuntu 18.04 LTS 72.0.1+build1-0ubuntu0.18.04.1
  • firefox Ubuntu 20.04 LTS 72.0.1+build1-0ubuntu1

ubuntu advisories UBUNTU-CVE-2019-17023

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

  • nss RHEL 7 3.53.1-3.el7_9
  • nspr RHEL 7 4.25.0-2.el7_9
  • nss-util RHEL 7 3.53.1-1.el7_9
  • nss-tools RHEL 7 3.53.1-3.el7_9
  • nss-softokn RHEL 7 3.53.1-6.el7_9
  • nss-sysinit RHEL 7 3.53.1-3.el7_9
  • nss-softokn-freebl RHEL 7 3.53.1-6.el7_9
  • nss RHEL 8 3.53.1-11.el8_2

red hat advisories RHSA-2020:4076RHSA-2020:3280

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

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

  • nspr Rocky Linux 8 4.25.0-2.el8_2

rocky linux advisories RLSA-2020:3280

  • nss Alpine 3.24, Alpine 3.23, Alpine 3.22 +10 more 3.49-r0
  • firefox Alpine 3.23, Alpine 3.22, Alpine 3.21 +9 more 71.0.1-r0
  • librewolf Alpine 3.24, Alpine 3.23, Alpine 3.22 +1 more 71.0.1-r0

alpine advisories ALPINE-CVE-2019-17023

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • firefox Arch Linux 72.0-1

arch linux advisories AVG-1084

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2019-17023 updated cvss 5.3

nss: TLS 1.3 HelloRetryRequest downgrade request sets client into invalid state

  • Red Hat Enterprise Linux 5 nss Red Hat Enterprise Linux 6 nss, nss-tools, nss-sysinit
    affected: no fix planned “Out of support scope”
  • Red Hat OpenShift Do 1 openshiftdo/odo-init-image-rhel7 1.1.3-2
    fixed: vendor fix RHSA-2021:0949
  • Red Hat Enterprise Linux AppStream (v. 8) nspr 4.25.0-2.el8_2, nss 3.53.1-11.el8_2, nss-util 3.53.1-11.el8_2, nss-tools 3.53.1-11.el8_2, nss-softokn 3.53.1-11.el8_2, nss-sysinit 3.53.1-11.el8_2, +1 more
    fixed: vendor fix RHSA-2020:3280
  • Red Hat Enterprise Linux Client (v. 7) nss 3.53.1-3.el7_9, nspr 4.25.0-2.el7_9, nss-util 3.53.1-1.el7_9, nss-tools 3.53.1-3.el7_9, nss-softokn 3.53.1-6.el7_9, nss-sysinit 3.53.1-3.el7_9, +1 more Red Hat Enterprise Linux Client Optional (v. 7) nss-devel 3.53.1-3.el7_9, nspr-devel 4.25.0-2.el7_9, nss-debuginfo 3.53.1-3.el7_9, nspr-debuginfo 4.25.0-2.el7_9, nss-util-devel 3.53.1-1.el7_9, nss-pkcs11-devel 3.53.1-3.el7_9, +4 more Red Hat Enterprise Linux ComputeNode Optional (v. 7) nss-devel 3.53.1-3.el7_9, nspr-devel 4.25.0-2.el7_9, nss-debuginfo 3.53.1-3.el7_9, nspr-debuginfo 4.25.0-2.el7_9, nss-util-devel 3.53.1-1.el7_9, nss-pkcs11-devel 3.53.1-3.el7_9, +4 more Red Hat Enterprise Linux Server (v. 7) nss 3.53.1-3.el7_9, nspr 4.25.0-2.el7_9, nss-util 3.53.1-1.el7_9, nss-tools 3.53.1-3.el7_9, nss-softokn 3.53.1-6.el7_9, nss-sysinit 3.53.1-3.el7_9, +1 more Red Hat Enterprise Linux Server Optional (v. 7) nss-debuginfo 3.53.1-3.el7_9, nss-pkcs11-devel 3.53.1-3.el7_9 Red Hat Enterprise Linux Workstation (v. 7) nss 3.53.1-3.el7_9, nspr 4.25.0-2.el7_9, nss-util 3.53.1-1.el7_9, nss-tools 3.53.1-3.el7_9, nss-softokn 3.53.1-6.el7_9, nss-sysinit 3.53.1-3.el7_9, +1 more
    +1 more products
    Red Hat Enterprise Linux Workstation Optional (v. 7) nss-debuginfo 3.53.1-3.el7_9, nss-pkcs11-devel 3.53.1-3.el7_9
    fixed: vendor fix RHSA-2020:4076

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.34% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
NVD 2.0 4.3 AV:N/AC:M/Au:N/C:N/I:P/A:N

Affected products

  • Mozilla Firefox

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.