Vulnerability in Musl-Libc Musl

CVE-2026-40200

An issue was discovered in musl libc 0.7.10 through 1.2.6. Stack-based memory corruption can occur during qsort of very large arrays, due to incorrectly implemented double-word primitives. The number of elements must exceed about seven million, i.e., the 32nd Leonardo number on 32-bit platforms (or the 64th Leonardo number on 64-bit platforms, which is not practical).

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.002 (5.8th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 5.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-40200: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-40200?
CVE-2026-40200 is a high-severity vulnerability in Musl-Libc Musl, classified under Always-Incorrect Control Flow Implementation. CVSS score: 8.1/10. Published 2026-04-10.
How severe is CVE-2026-40200?
High severity. CVSS v3 base score is 8.1 out of 10.