# CVE-2019-17026

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.

- Page: https://www.vulneraibility.com/cve/CVE-2019-17026
- CVSS: 8.8
- Known exploited: yes, in CISA KEV since 2021-11-03; CISA due date 2022-05-03
- EPSS: 46.31% (percentile 98.8)
- Public exploit code: 1 on Exploit-DB · 2 GitHub proofs of concept (first 2020-08-27)
- CISA SSVC: exploitation active, automatable no, technical impact total (assessed 2025-02-07)
- Weakness: CWE-843
- Published: 2020-03-02

## Affected versions

- Mozilla Firefox: affected < 72.0.1
- Mozilla Firefox ESR: affected < 68.4.1
- Mozilla Thunderbird: affected < 68.4.1

A version outside these ranges is not a statement that it is unaffected.

## References

- [other] https://www.mozilla.org/security/advisories/mfsa2020-04/
- [other] https://www.mozilla.org/security/advisories/mfsa2020-03/
- [other] https://bugzilla.mozilla.org/show_bug.cgi?id=1607443
- [advisory] https://security.gentoo.org/glsa/202003-02
- [advisory] https://usn.ubuntu.com/4335-1/
- [other] http://packetstormsecurity.com/files/162568/Firefox-72-IonMonkey-JIT-Type-Confusion.html
- [other] https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-17026

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.