CVE-2023-6246
CVE-2023-6246 is a high-severity vulnerability in Gnu Glibc with a CVSS 3.x base score of 8.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: High (CVSS 3.x base score 8.4)
- EPSS exploit prediction: 5% (91st percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2023-58491
- Weakness: CWE-787
- Affected product: Gnu Glibc
- Published:
- Last modified:
Description
A 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 the openlog function was not called, or called with the ident argument set to NULL, and the program name (the basename of argv[0]) is bigger than 1024 bytes, resulting in an application crash or local privilege escalation. This issue affects glibc 2.36 and newer.
Frequently asked questions
- What is CVE-2023-6246?
- A 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 the openlog function was not called, or called with the ident argument set to NULL, and the program name (the basename of argv[0]) is bigger than 1024 bytes, resulting in an application crash or local privilege escalation. This issue affects glibc 2.36 and newer.
- How severe is CVE-2023-6246?
- CVE-2023-6246 has a CVSS 3.x base score of 8.4, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2023-6246 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-6246?
- CVE-2023-6246 primarily affects Gnu Glibc. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2023-6246?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2023-6246 have an EU (EUVD) identifier?
- Yes. CVE-2023-6246 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-58491.
- When was CVE-2023-6246 published?
- CVE-2023-6246 was published on 2024-01-31 and last updated on 2026-06-17.
References
- http://packetstormsecurity.com/files/176931/glibc-qsort-Out-Of-Bounds-Read-Write.html
- http://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html
- http://seclists.org/fulldisclosure/2024/Feb/3
- http://seclists.org/fulldisclosure/2024/Feb/5
- https://access.redhat.com/security/cve/CVE-2023-6246
- https://bugzilla.redhat.com/show_bug.cgi?id=2249053
- https://lists.fedoraproject.org/archives/list/[email protected]/message/D2FIH77VHY3KCRROCXOT6L27WMZXSJ2G/
- https://lists.fedoraproject.org/archives/list/[email protected]/message/MWQ6BZJ6CV5UAW4VZSKJ6TO4KIW2KWAQ/
- https://security.gentoo.org/glsa/202402-01
- https://security.netapp.com/advisory/ntap-20240216-0007/
- https://www.openwall.com/lists/oss-security/2024/01/30/6
- https://www.qualys.com/2024/01/30/cve-2023-6246/syslog.txt
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
Affected products (3)
- cpe:2.3:a:gnu:glibc:*:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:*
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