CVE-2023-6780: glibc Integer Overflow — Exploit

Description

An integer 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 very long message, leading to an incorrect calculation of the buffer size to store the message, resulting in undefined behavior. This issue affects glibc 2.37 and newer.

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CVSS v3.1 Score

5.3

MEDIUM

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

Weakness Type (CWE)

CWE-131 CWE-131

CWE-190 Integer Overflow

Affected Products

Vendor	Product	Versions
gnu	glibc	2.37 — 2.39
fedoraproject	fedora	All
fedoraproject	fedora	All

References

Exploits

http://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html http://seclists.org/fulldisclosure/2024/Feb/3 https://www.openwall.com/lists/oss-security/2024/01/30/6 http://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html http://seclists.org/fulldisclosure/2024/Feb/3 https://www.openwall.com/lists/oss-security/2024/01/30/6

Other References

https://access.redhat.com/security/cve/CVE-2023-6780 https://bugzilla.redhat.com/show_bug.cgi?id=2254396 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://www.qualys.com/2024/01/30/cve-2023-6246/syslog.txt https://access.redhat.com/security/cve/CVE-2023-6780 https://bugzilla.redhat.com/show_bug.cgi?id=2254396 https://lists.fedoraproject.org/archives/list/[email protected]/message/D2FIH77VHY3KCRROCXOT6L27WMZXSJ2G/ https://lists.fedoraproject.org/archives/list/[email protected]/message/MWQ6BZJ6CV5UAW4VZSKJ6TO4KIW2KWAQ/

Frequently Asked Questions

What is CVE-2023-6780? +

An integer 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 very long message, leading to an incorrect calculation of the buffer size to store the message, resulting in undefined behavior. This issue affects glibc 2.37 and newer. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2023-6780? +

CVE-2023-6780 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2023-6780? +

CVE-2023-6780 affects products from fedoraproject, gnu, specifically: fedora, glibc. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-6780? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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