# CVE-2026-10702 — Mozilla Firefox

> As of 2026-07-15, CVE-2026-10702 is a MEDIUM-severity vulnerability in Mozilla Firefox, CVSS v3.1 4.3, EPSS 0.5% (42.5th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-10702, most recently “IonStack: One-Click Firefox JIT-to-Linux-Kernel Root Exploit Chain (CVE-2026-10702 + CVE-2026-43499 "GhostLock") Demonstrated Against Android 17”.

**Last updated:** 2026-07-15

## What is CVE-2026-10702?

JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 151.0.3.

The record classifies CVE-2026-10702 under weakness classes [CWE-843](https://cwe.mitre.org/data/definitions/843.html), [CWE-733](https://cwe.mitre.org/data/definitions/733.html). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs a user to take an action first. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 103 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 4.3 — MEDIUM (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L`)
- **EPSS (FIRST):** 0.5% probability of exploitation in the next 30 days, higher than 42.5% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 3.9/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-06-02, last modified 2026-07-15

## Is CVE-2026-10702 being exploited?

No public exploitation evidence for CVE-2026-10702 is recorded in the sources Threadlinqs tracks — CISA KEV, Exploit-DB, public proof-of-concept repositories and ProjectDiscovery Nuclei — as of 2026-07-15. That is an absence of evidence in those feeds, not a guarantee that the vulnerability is unexploited.

## Affected products and versions

- **Mozilla**: Firefox

## How to fix CVE-2026-10702

Vendor advisory: [https://www.mozilla.org/security/advisories/mfsa2026-54/](https://www.mozilla.org/security/advisories/mfsa2026-54/). Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.

## Threat activity tracking CVE-2026-10702

1 tracked threat in the Threadlinqs corpus references CVE-2026-10702, either in the campaign’s CVE list or as an indicator on the campaign record.

- [IonStack: One-Click Firefox JIT-to-Linux-Kernel Root Exploit Chain (CVE-2026-10702 + CVE-2026-43499 "GhostLock") Demonstrated Against Android 17](https://intel.threadlinqs.com/threat/TL-2026-1477) — HIGH · 2026-07-18

## Sources

Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on 2026-07-18. This product uses the NVD API but is not endorsed or certified by the NVD.

**Other references**

- [bugzilla.mozilla.org](https://bugzilla.mozilla.org/show_bug.cgi?id=2040903)
- [mozilla.org](https://www.mozilla.org/security/advisories/mfsa2026-54/)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-10702
Full detection coverage and IOCs for threats exploiting CVE-2026-10702 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp