CVE-2023-4911: Local Privilege Escalation in glibc’s ld.so | Qualys

Summary: Qualys Threat Research Unit discovered a buffer overflow in glibc's dynamic loader when processing the GLIBC_TUNABLES environment variable, and exploited it to gain full root privileges on default installations of Fedora 37 and 38, Ubuntu 22.04 and 23.04, and Debian 12 and 13. The flaw was introduced in April 2021; Alpine Linux is not affected because it uses musl libc instead of glibc.
Why it matters: Qualys is withholding its exploit code, but states the buffer overflow can be turned into a data-only attack with ease, meaning other research teams could release exploits soon - and glibc's dynamic loader runs with elevated privileges whenever a local user launches a set-user-ID or set-group-ID program.

Read the original at Qualys Blog ↗

Topics: Vulnerabilities & Patching
Mentions: CVE-2023-4911
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