CVEs / CVE-2019-17026
CVE-2019-17026: Mozilla Firefox And Thunderbird Type Confusion Vulnerability
- Known exploited in the CISA KEV catalog since 3 Nov 2021
- high 8.8 CVSS 3.1 (NVD)
- EPSS 46.3% chance of exploitation in the next 30 days, higher than 98% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Mozilla Firefox and Thunderbird contain a type confusion vulnerability due to incorrect alias information in the IonMonkey JIT compiler when setting array elements.
Description
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.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Mozilla Firefox ESR | from unspecified, before 68.4.1 | 68.4.1 |
| Mozilla Thunderbird | from unspecified, before 68.4.1 | 68.4.1 |
| Mozilla Firefox | from unspecified, before 72.0.1 | 72.0.1 |
Exploitation
| In CISA KEV since | 3 Nov 2021 |
|---|---|
| Due date for US federal agencies | 3 May 2022 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 3.1 | 8.8 highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-843 |
References
- CVE-2019-17026 on NVD
- CVE-2019-17026 in the CISA KEV catalog
- CVE-2019-17026 on OSV
- http://packetstormsecurity.com/files/162568/Firefox-72-IonMonkey-JIT-Type-Confusion.html Exploit, Third Party Advisory, VDB Entry
- https://bugzilla.mozilla.org/show_bug.cgi?id=1607443 Issue Tracking
- https://security.gentoo.org/glsa/202003-02 Third Party Advisory
- https://usn.ubuntu.com/4335-1/ Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-03/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-04/ Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-17026 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.