PatchTheCVECVE-2025-62493: A vulnerability exists in the QuickJS engine's BigInt string conversion logic (js_bigint_to_string1) due to an
CVE-2025-62493 is a medium-severity flaw (CVSS 6.5) affecting quickjs. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
A vulnerability exists in the QuickJS engine's BigInt string conversion logic (js_bigint_to_string1) due to an incorrect calculation of the required number of digits, which in turn leads to reading memory past the allocated BigInt structure. * The function determines the number of characters (n_digits) needed for the string representation by calculating: $$ \\ \text{n\_digits} = (\text{n\_bits} + \text{log2\_radix} - 1) / \text{log2\_radix}$
Why this priority
- Public exploit reference
A fixed release or distro patch exists.
Risk facts
| CVSS score | 6.5 (Medium) |
| Attack vector | Adjacent network |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.4% (top 68%) |
| CISA exploited list | No |
| Weakness | CWE-125 |
| 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-2025-62493?
quickjs: upgrade to 2025-09-13. Exact commands for each OS are on this page.
Is CVE-2025-62493 being exploited?
CVE-2025-62493 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-2025-62493 affect?
CVE-2025-62493 affects quickjs. Severity is medium (CVSS 6.5). A vulnerability exists in the QuickJS engine's BigInt string conversion logic (js_bigint_to_string1) due to an incorrect calculation of the required number of digits, which in turn leads to reading memory past the allocated BigInt structure
How urgent is CVE-2025-62493?
Priority 36/100. Public exploit reference
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