High severity · published Jan 31, 2024
CVE-2023-6779
Glibc: off-by-one heap-based buffer overflow in __vsyslog_internal()
7.5
CVSS
3.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.2% · higher than 88% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FE
Fedora · Fedoraproject
38; 39 · source: vendor, NVD
GL
Glibc · Gnu
2.37 before 2.39 · source: NVD
SS
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.5; V3.1.5 · source: CISA
SS
SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens
V3.1.5; V3.1.5 · source: CISA
SS
SIPLUS S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.5 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-6779
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-6779
Exploit
http://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html
Exploit
http://seclists.org/fulldisclosure/2024/Feb/3
Third Party Advisory
https://access.redhat.com/security/cve/CVE-2023-6779
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2254395
Mailing List
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/D2FIH77VHY3KCRROCXOT6L27WMZXSJ2G/
Mailing List
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MWQ6BZJ6CV5UAW4VZSKJ6TO4KIW2KWAQ/
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