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Fencer Intel
high 8.8

CVE-2019-17026 kev in the critical feed json

Incorrect alias information in IonMonkey JIT compiler for setting array elements could lead to a type confusion.

published 6y ago modified 4mo ago also EUVD-2019-7500

cvss
8.8
version 3.1, CNA
cisa kev
Exploited
added 2021-11-03
epss
46.3%
EPSS 46.3% chance of exploitation in 30 days, percentile 98%
public exploits
1
Exploit-DB

Summary

Incorrect alias information in IonMonkey JIT compiler for setting array elements could lead to a type confusion. We are aware of targeted attacks in the wild abusing this flaw. This vulnerability affects Firefox ESR < 68.4.1, Thunderbird < 68.4.1, and Firefox < 72.0.1.

Patch / fix

cisa required action Apply updates per vendor instructions.

  • Mozilla Firefox ESR 68.4.1
  • Mozilla Thunderbird 68.4.1
  • Mozilla Firefox 72.0.1
  • firefox-esr Debian 14, Debian 13, Debian 12 68.4.1esr-1
  • thunderbird Debian 14, Debian 13, Debian 12 1:68.4.1-1

debian advisories DEBIAN-CVE-2019-17026

  • 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
  • thunderbird Ubuntu 16.04 LTS 1:68.7.0+build1-0ubuntu0.16.04.2
  • thunderbird Ubuntu 18.04 LTS 1:68.4.1+build1-0ubuntu0.18.04.1
  • thunderbird Ubuntu 20.04 LTS 1:68.4.1+build1-0ubuntu1

ubuntu advisories UBUNTU-CVE-2019-17026

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

  • thunderbird RHEL 6 68.4.1-2.el6_10
  • thunderbird RHEL 7 68.4.1-2.el7_7
  • thunderbird RHEL 8 68.4.1-2.el8_1
  • firefox RHEL 8 68.4.1-1.el8_1
  • firefox RHEL 6 68.4.1-1.el6_10
  • firefox RHEL 7 68.4.1-1.el7_7
  • firefox RHEL 8.0 E4S 68.4.1-1.el8_0
  • thunderbird RHEL 8.0 E4S 68.4.1-2.el8_0

red hat advisories RHSA-2020:0295RHSA-2020:0292RHSA-2020:0123RHSA-2020:0120RHSA-2020:0127RHSA-2020:0111

  • MozillaThunderbird SLE Workstation Extension 15 SP1, SLE Workstation Extension 15 68.4.1-3.66.1
  • MozillaFirefox SLE Module for Desktop Applications 15 SP1, SLE Module for Desktop Applications 15 68.4.1-3.66.1
  • MozillaFirefox SLES for SAP 12 SP5, SLES for SAP 12 SP4, SLES for SAP 12 SP3 +17 more 68.4.1-109.101.1
  • MozillaFirefox SLES 11 SP4-LTSS 68.4.1-78.57.1

suse advisories SUSE-SU-2020:0142-1SUSE-SU-2020:0078-1SUSE-SU-2020:14268-1SUSE-SU-2020:0068-1

  • firefox-esr openSUSE Tumbleweed 128.5.1-1.1
  • MozillaFirefox openSUSE Tumbleweed 92.0-1.2
  • MozillaThunderbird openSUSE Tumbleweed 91.1.1-1.1
  • MozillaThunderbird openSUSE Leap 15.1 68.4.1-lp151.2.22.2
  • MozillaFirefox openSUSE Leap 15.1 68.4.1-lp151.2.24.1

opensuse advisories openSUSE-SU-2024:14572-1openSUSE-SU-2024:10600-1openSUSE-SU-2024:10601-1openSUSE-SU-2020:0094-1openSUSE-SU-2020:0060-1

  • 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
  • firefox-esr Alpine 3.23, Alpine 3.22, Alpine 3.21 +10 more 68.4.1-r0

alpine advisories ALPINE-CVE-2019-17026

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 72.0.1-1
  • thunderbird Arch Linux 68.4.1-1

arch linux advisories AVG-1085AVG-1086

Is CVE-2019-17026 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

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-2019-17026 updated cvss 8.8

Mozilla: IonMonkey type confusion with StoreElementHole and FallibleStoreElement

  • Red Hat Enterprise Linux 5 firefox, thunderbird
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux AppStream (v. 8) firefox 68.4.1-1.el8_1, thunderbird 68.4.1-2.el8_1
    fixed: vendor fix RHSA-2020:0111
  • Red Hat Enterprise Linux AppStream E4S (v. 8.0) firefox 68.4.1-1.el8_0, thunderbird 68.4.1-2.el8_0
    fixed: vendor fix RHSA-2020:0295
  • Red Hat Enterprise Linux Client (v. 7) firefox 68.4.1-1.el7_7, thunderbird 68.4.1-2.el7_7 Red Hat Enterprise Linux Client Optional (v. 7) firefox 68.4.1-1.el7_7
    fixed: vendor fix RHSA-2020:0085
  • Red Hat Enterprise Linux Desktop (v. 6) firefox 68.4.1-1.el6_10, thunderbird 68.4.1-2.el6_10 Red Hat Enterprise Linux Desktop Optional (v. 6) firefox 68.4.1-1.el6_10 Red Hat Enterprise Linux HPC Node Optional (v. 6) firefox 68.4.1-1.el6_10 Red Hat Enterprise Linux Server (v. 6) firefox 68.4.1-1.el6_10
    fixed: vendor fix RHSA-2020:0086
  • Red Hat Enterprise Linux Server (v. 7) firefox 68.4.1-1.el7_7
    fixed: vendor fix RHSA-2020:0085
  • Red Hat Enterprise Linux Server Optional (v. 6) firefox 68.4.1-1.el6_10, thunderbird 68.4.1-2.el6_10
    fixed: vendor fix RHSA-2020:0086
  • Red Hat Enterprise Linux Server Optional (v. 7) firefox 68.4.1-1.el7_7, thunderbird 68.4.1-2.el7_7
    fixed: vendor fix RHSA-2020:0085
show 4 more
  • Red Hat Enterprise Linux Workstation (v. 6) firefox 68.4.1-1.el6_10, thunderbird 68.4.1-2.el6_10
    fixed: vendor fix RHSA-2020:0086
  • Red Hat Enterprise Linux Workstation (v. 7) firefox 68.4.1-1.el7_7, thunderbird 68.4.1-2.el7_7
    fixed: vendor fix RHSA-2020:0085
  • Red Hat Enterprise Linux Workstation Optional (v. 6) firefox 68.4.1-1.el6_10
    fixed: vendor fix RHSA-2020:0086
  • Red Hat Enterprise Linux Workstation Optional (v. 7) firefox 68.4.1-1.el7_7
    fixed: vendor fix RHSA-2020:0085

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

Timeline

  1. Found exploited as a 0-day (Project Zero)
  2. 0-day patched (Project Zero)
  3. Published
  4. First public exploit (EDB-49864)
  5. Added to CISA KEV
  6. CISA patch deadline
  7. CISA SSVC: exploitation active

Known exploited

Added
5y ago
Patch by
2022-05-03 (4y ago)
Ransomware
Not known
Required action
Apply updates per vendor instructions.
Vendor, product
Mozilla, Firefox and Thunderbird
CISA name
Mozilla Firefox And Thunderbird Type Confusion Vulnerability

Zero-day

Detected in real attacks while still unknown to the vendor and the public, per Google Project Zero's 0day In-the-Wild tracker.

Found
2020-01-07
Patched
2020-01-08
Details
project zero root cause analysis

CISA SSVC

Exploitation
Active, exploited in the wild
Automatable
no
Technical impact
total
Assessed
last yr.

Exploit prediction

46.31% chance of exploitation in the next 30 days, higher than 98% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • EDB-49864 Firefox 72 IonMonkey - JIT Type Confusion local, 2021-05-13
  • packetstormsecurity.com http://packetstormsecurity.com/files/162568/Firefox-72-IonMonkey-JIT-Type-Confusion.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CISA ADP 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CNA 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD 2.0 6.8 AV:N/AC:M/Au:N/C:P/I:P/A:P

Affected products

  • Mozilla Firefox ESR
  • Mozilla Thunderbird
  • Mozilla Firefox

Classification

Weakness
  • CWE-843 Access of Resource Using Incompatible Type

References

Sources

Fencer Intel 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.