Description
An off-by-one heap-based buffer overflow was found in the __vsyslog_internal function of the glibc library. This function is called by the syslog and vsyslog functions. This issue occurs when these functions are called with a message bigger than INT_MAX bytes, leading to an incorrect calculation of the buffer size to store the message, resulting in an application crash. This issue affects glibc 2.37 and newer.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | glibc | — | 2.39 |
| Red Hat | Red Hat Enterprise Linux 6 | — | — |
| Red Hat | Red Hat Enterprise Linux 7 | — | — |
| Red Hat | Red Hat Enterprise Linux 8 | — | — |
| Red Hat | Red Hat Enterprise Linux 9 | — | — |
| Fedora | Fedora | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | glibc | 2.37-15 | — |
| Debian 13 | glibc | 2.37-15 | — |
| Debian 12 | glibc | 2.36-9+deb12u4 | DSA-5611-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | glibc | 2.39-0ubuntu1 | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | glibc | 2.38-6 | — |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | glibc | 2.38-r11 | — |
Advisories 5
- SSA-082556 SSA-082556: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1.5 Siemens ProductCERT · Oct 13, 2026
- WID-SEC-2024-0246 GNU libc: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 15, 2026
- ICSA-25-162-05 Siemens SIMATIC S7-1500 CPU family CISA ICS & IT advisories · May 14, 2026
- DSA-5611-1 glibc - security update Debian Security (DSA / DLA) · Mar 9, 2026
- NCSC-2025-0187 Kwetsbaarheden verholpen in Siemens producten NCSC-NL (Netherlands) · Jun 10, 2025
References
- http://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html
- http://seclists.org/fulldisclosure/2024/Feb/3
- https://access.redhat.com/security/cve/CVE-2023-6779 vdb-entry
- RHBZ#2254395 issue-tracking
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/D2FIH77VHY3KCRROCXOT6L27WMZXSJ2G/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MWQ6BZJ6CV5UAW4VZSKJ6TO4KIW2KWAQ/
- https://security.gentoo.org/glsa/202402-01
- https://www.openwall.com/lists/oss-security/2024/01/30/6
- https://www.qualys.com/2024/01/30/cve-2023-6246/syslog.txt
- https://security.netapp.com/advisory/ntap-20240223-0006/