Stack overflow via select() file descriptor set overflow_CVE-2026-39457

7.8 / 10

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Description

When exchanging data over a socket, libnv uses select(2) to wait for data to arrive. However, it does not verify whether the provided socket descriptor fits in select(2)'s file descriptor set size limit of FD_SETSIZE (1024).

An attacker who is able to force a libnv application to allocate large file descriptors, e.g., by opening many descriptors and executing a program which is not careful to close them upon startup, can trigger stack corruption. If the target application is setuid-root, then this could be used to elevate local privileges.

Basic Information

ID CVE-2026-39457

Source freebsd

Published Apr 30, 2026 at 08:01

Modified Apr 30, 2026 at 13:11

Affected Product

Vendor FreeBSD

Product FreeBSD

Version 15.0-RELEASE

Affected Versions FreeBSD FreeBSD 15.0-RELEASE
FreeBSD FreeBSD 14.4-RELEASE
FreeBSD FreeBSD 14.3-RELEASE
FreeBSD FreeBSD 13.5-RELEASE

CWE Classification

CWE-121

References

security.freebsd.org /advisories/FreeBSD-SA-26:16.libnv.asc

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    "published": "2026-04-30T08:01:49.015Z",
    "modified": "2026-04-30T13:11:29.677Z",
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