CVE-2023-6779 Glibc: off-by-one heap-based buffer overflow in __vsyslog_internal()

What is CVE-2023-6779?

CVE-2023-6779 is a high-severity memory corruption vulnerability in Fedoraproject Fedora, published on 31 Jan 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Weakness: CWE-787, CWE-122

Which versions are affected by CVE-2023-6779?

It affects 2 products.

Products include Fedoraproject Fedora, Gnu Glibc.

How do I fix CVE-2023-6779?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2023-6779 being exploited?

There is no known exploitation of CVE-2023-6779 in the wild and no public exploit code.

Other vulnerabilities in Fedoraproject Fedora

• CVE-2024-4577 PHP-CGI OS Command Injection Exploited Critical 9.8
• CVE-2021-39226 Grafana Authentication Bypass Exploited Critical 9.8
• CVE-2019-5544 VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow Exploited Critical 9.8
• CVE-2024-4947 Google Chromium V8 Type Confusion Exploited Critical 9.6
• CVE-2024-4671 Google Chromium Visuals Use-After-Free Exploited Critical 9.6

All Fedoraproject Fedora vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-34736, BELL-CVE-2023-6779, DEBIAN-CVE-2023-6779, GHSA-p5vr-h433-qhqr, UBUNTU-CVE-2023-6779.