libc stdio buffer overflow

Description

In versions of FreeBSD 12.4-RELEASE prior to 12.4-RELEASE-p7 and FreeBSD 13.2-RELEASE prior to 13.2-RELEASE-p5 the __sflush() stdio function in libc does not correctly update FILE objects' write space members for write-buffered streams when the write(2) system call returns an error.  Depending on the nature of an application that calls libc's stdio functions and the presence of errors returned from the write(2) system call (or an overridden stdio write routine) a heap buffer overflow may occur. Such overflows may lead to data corruption or the execution of arbitrary code at the privilege level of the calling program.

Scores

EPSS (exploitation in 30 days)

1.1% · top 35% of all CVEs (6 Nov 2026)

The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.

Weakness

• CWE-787 Out-of-bounds Write (opens in a new tab)All about CWE-787 and its CVEs
• CWE-131 Incorrect Calculation of Buffer Size (opens in a new tab)All about CWE-131 and its CVEs

Affected products

• FreeBSD · FreeBSD

  • affected 12.4-RELEASE – < p7
  • affected 13.2-RELEASE – < p5

References (2)

• https://security.freebsd.org/advisories/FreeBSD-SA-23:15.stdio.asc (opens in a new tab)vendor-advisoryx_transferred
• https://security.netapp.com/advisory/ntap-20231214-0004/ (opens in a new tab)x_transferred

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2023-5941](https://trackcve.app/badge/CVE-2023-5941.svg)](https://trackcve.app/cve/CVE-2023-5941)

Record last updated 13 Feb 2025, 17:25 UTC.