PatchTheCVECVE-2025-62494: A type confusion vulnerability exists in the handling of the string addition (+) operation within the QuickJS
CVE-2025-62494 is a high-severity flaw (CVSS 8.8) affecting quickjs. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
A type confusion vulnerability exists in the handling of the string addition (+) operation within the QuickJS engine. * The code first checks if the left-hand operand is a string. * It then attempts to convert the right-hand operand to a primitive value using JS_ToPrimitiveFree. This conversion can trigger a callback (e.g., toString or valueOf). * During this callback, an attacker can modify the type of the left-hand operand in memo
Why this priority
- High severity
- Public exploit reference
A fixed release or distro patch exists.
Risk facts
| CVSS score | 8.8 (High) |
| Attack vector | Adjacent network |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.5% (top 56%) |
| CISA exploited list | No |
| Weakness | CWE-704 |
| Published | 2025-10-16 |
| Last modified | 2026-10-19 |
Last updated 2026-10-19 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2025-62494?
quickjs: upgrade to 2025-09-13. Exact commands for each OS are on this page.
Is CVE-2025-62494 being exploited?
CVE-2025-62494 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2025-62494 affect?
CVE-2025-62494 affects quickjs. Severity is high (CVSS 8.8). A type confusion vulnerability exists in the handling of the string addition (+) operation within the QuickJS engine. * The code first checks if the left-hand operand is a string. * It then attempts to convert the right-hand operan
How urgent is CVE-2025-62494?
Priority 47/100. High severity; Public exploit reference
Related CVEs
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