CVE-2023-45679 in stb_vorbis
Summary
by MITRE • 10/25/2023
stb_vorbis is a single file MIT licensed library for processing ogg vorbis files. A crafted file may trigger memory allocation failure in `start_decoder`. In that case the function returns early, but some of the pointers in `f->comment_list` are left initialized and later `setup_free` is called on these pointers in `vorbis_deinit`. This issue may lead to code execution.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 04/21/2025
The vulnerability identified as CVE-2023-45679 affects stb_vorbis, a widely-used single-file MIT licensed library designed for processing ogg vorbis audio files. This library is commonly integrated into various applications and systems that handle audio processing, making the vulnerability potentially impactful across multiple software ecosystems. The issue resides within the decoder's initialization function where improper memory management leads to a critical flaw in the library's error handling mechanism.
The technical flaw manifests in the `start_decoder` function where a memory allocation failure can cause an early return without properly cleaning up all allocated resources. Specifically, pointers within the `f->comment_list` structure remain initialized even after the function exits prematurely due to allocation failure. This memory management inconsistency creates a scenario where `setup_free` is subsequently called on these uninitialized pointers during the `vorbis_deinit` process. The improper cleanup leads to a classic use-after-free condition that can be exploited by malicious actors to execute arbitrary code within the context of the vulnerable application.
The operational impact of this vulnerability extends beyond simple memory corruption as it represents a serious security flaw that can be leveraged for remote code execution. Attackers can craft specially malformed ogg vorbis files that trigger the memory allocation failure condition, subsequently exploiting the uninitialized pointer dereference during cleanup operations. This vulnerability aligns with CWE-415, which describes double free conditions, and CWE-416, which covers use after free errors, both of which are fundamental memory safety issues that have been extensively documented in cybersecurity literature. The attack surface is particularly concerning given that stb_vorbis is embedded in numerous applications across different platforms and operating systems.
Mitigation strategies should focus on immediate code updates and defensive programming practices to address this vulnerability. The most effective approach involves applying the latest patches from the stb_vorbis maintainers that properly handle memory allocation failures and ensure complete cleanup of all allocated resources during error conditions. Organizations should implement input validation and sanitization measures when processing audio files, particularly those from untrusted sources. Additionally, the vulnerability demonstrates the importance of following secure coding practices such as the principle of least privilege and proper resource management, which are fundamental concepts in the software security framework. The issue also highlights the need for comprehensive testing including fuzzing and memory safety analysis to identify similar vulnerabilities in embedded libraries that are critical to application security. This vulnerability exemplifies why adherence to security standards and regular security assessments are essential for maintaining robust software systems.