CVE Vulnerabilities

CVE-2024-24577

Heap-based Buffer Overflow

Published: Feb 06, 2024 | Modified: Nov 21, 2024
CVSS 3.x
9.8
CRITICAL
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
RedHat/V2
RedHat/V3
9.8 IMPORTANT
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Ubuntu
MEDIUM

libgit2 is a portable C implementation of the Git core methods provided as a linkable library with a solid API, allowing to build Git functionality into your application. Using well-crafted inputs to git_index_add can cause heap corruption that could be leveraged for arbitrary code execution. There is an issue in the has_dir_name function in src/libgit2/index.c, which frees an entry that should not be freed. The freed entry is later used and overwritten with potentially bad actor-controlled data leading to controlled heap corruption. Depending on the application that uses libgit2, this could lead to arbitrary code execution. This issue has been patched in version 1.6.5 and 1.7.2.

Weakness

A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

Affected Software

Name Vendor Start Version End Version
Libgit2 Libgit2 * 1.6.5 (excluding)
Libgit2 Libgit2 1.7.0 (including) 1.7.2 (excluding)
Libgit2 Ubuntu bionic *
Libgit2 Ubuntu esm-apps/bionic *
Libgit2 Ubuntu esm-apps/xenial *
Libgit2 Ubuntu esm-infra-legacy/trusty *
Libgit2 Ubuntu focal *
Libgit2 Ubuntu jammy *
Libgit2 Ubuntu mantic *
Libgit2 Ubuntu trusty *
Libgit2 Ubuntu trusty/esm *
Libgit2 Ubuntu xenial *

Potential Mitigations

  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking.
  • D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] discusses canary-based detection in detail.
  • Run or compile the software using features or extensions that randomly arrange the positions of a program’s executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code.
  • Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Imported modules may be similarly realigned if their default memory addresses conflict with other modules, in a process known as “rebasing” (for Windows) and “prelinking” (for Linux) [REF-1332] using randomly generated addresses. ASLR for libraries cannot be used in conjunction with prelink since it would require relocating the libraries at run-time, defeating the whole purpose of prelinking.
  • For more information on these techniques see D3-SAOR (Segment Address Offset Randomization) from D3FEND [REF-1335].

References