CVE-2019-17026 : Incorrect alias information in IonMonkey JIT compiler for setting array elements

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.

Published 2020-03-02 05:15:12

Updated 2025-03-21 19:22:54

Source Mozilla Corporation

View at NVD, CVE.org

Products affected by CVE-2019-17026

Mozilla » Firefox
Versions before (<) 72.0.1
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
Matching versions
Mozilla » Firefox » ESR Edition
Versions before (<) 68.4.1
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
Matching versions
Mozilla » Thunderbird
Versions before (<) 68.4.1
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
Matching versions
Canonical » Ubuntu Linux » Version: 16.04 ESM Edition
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*
Matching versions

CVE-2019-17026 is in the CISA Known Exploited Vulnerabilities Catalog

CISA vulnerability name:

Mozilla Firefox And Thunderbird Type Confusion Vulnerability

CISA required action:

Apply updates per vendor instructions.

CISA description:

Mozilla Firefox and Thunderbird contain a type confusion vulnerability due to incorrect alias information in the IonMonkey JIT compiler when setting array elements.

Notes:

https://nvd.nist.gov/vuln/detail/CVE-2019-17026

Added on 2021-11-03 Action due date 2022-05-03

Exploit prediction scoring system (EPSS) score for CVE-2019-17026

EPSS FAQ

47.59%

Probability of exploitation activity in the next 30 days EPSS Score History

~ 98 %

Percentile, the proportion of vulnerabilities that are scored at or less

CVSS scores for CVE-2019-17026

Base Score	Base Severity	CVSS Vector	Exploitability Score	Impact Score	Score Source	First Seen
6.8	MEDIUM	AV:N/AC:M/Au:N/C:P/I:P/A:P	8.6	6.4	NIST
Access Vector: Network Access Complexity: Medium Authentication: None Confidentiality Impact: Partial Integrity Impact: Partial Availability Impact: Partial
8.8	HIGH	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H	2.8	5.9	134c704f-9b21-4f2e-91b3-4a467353bcc0	2025-02-07
Attack Vector: Network Attack Complexity: Low Privileges Required: None User Interaction: Required Scope: Unchanged Confidentiality: High Integrity: High Availability: High
8.8	HIGH	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H	2.8	5.9	NIST
Attack Vector: Network Attack Complexity: Low Privileges Required: None User Interaction: Required Scope: Unchanged Confidentiality: High Integrity: High Availability: High

CWE ids for CVE-2019-17026

CWE-843 Access of Resource Using Incompatible Type ('Type Confusion')

The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.
Assigned by:
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)
- nvd@nist.gov (Primary)

References for CVE-2019-17026

https://www.mozilla.org/security/advisories/mfsa2020-03/

Security Vulnerabilities fixed in Firefox 72.0.1 and Firefox ESR 68.4.1 — Mozilla
Vendor Advisory
https://security.gentoo.org/glsa/202003-02

Mozilla Firefox: Multiple vulnerabilities (GLSA 202003-02) — Gentoo security
Third Party Advisory

CVEs referencing this url
http://packetstormsecurity.com/files/162568/Firefox-72-IonMonkey-JIT-Type-Confusion.html

Firefox 72 IonMonkey JIT Type Confusion ≈ Packet Storm
Exploit;Third Party Advisory;VDB Entry
https://www.mozilla.org/security/advisories/mfsa2020-04/

Security Vulnerabilities fixed in Thunderbird 68.4.1 — Mozilla
Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1607443

Access Denied
Issue Tracking
https://usn.ubuntu.com/4335-1/

USN-4335-1: Thunderbird vulnerabilities | Ubuntu security notices
Third Party Advisory

CVEs referencing this url