CVE-2026-1110: cijliu librtsp Buffer Overflow Vulnerability

CVE-2026-1110 Overview

A buffer overflow vulnerability has been identified in cijliu librtsp, affecting the rtsp_parse_method function. This flaw allows an attacker with local access to manipulate input data in a way that triggers a buffer overflow condition, potentially leading to memory corruption and system instability. The vulnerability exists in versions up to commit 2ec1a81ad65280568a0c7c16420d7c10fde13b04.

Critical Impact

Local attackers can exploit this buffer overflow vulnerability in the rtsp_parse_method function to corrupt memory, potentially affecting confidentiality, integrity, and availability of the system.

Affected Products

• cijliu librtsp (up to commit 2ec1a81ad65280568a0c7c16420d7c10fde13b04)
• Systems utilizing librtsp for RTSP protocol parsing
• Applications integrating the vulnerable librtsp library

Discovery Timeline

• January 18, 2026 - CVE-2026-1110 published to NVD
• January 18, 2026 - Last updated in NVD database

Technical Details for CVE-2026-1110

Vulnerability Analysis

This vulnerability is classified as CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer). The buffer overflow occurs within the rtsp_parse_method function of the librtsp library, which is responsible for parsing RTSP method strings from incoming requests.

When processing RTSP method data, the function fails to properly validate the boundaries of the input buffer before performing operations on it. This improper boundary checking allows an attacker to supply crafted input that exceeds the expected buffer size, causing data to be written beyond the allocated memory region.

The vulnerability requires local access to exploit, meaning an attacker must have existing access to the target system. The librtsp project uses continuous delivery with rolling releases, which means there are no specific version numbers to identify vulnerable versus patched releases. The vendor was contacted about this vulnerability but did not respond.

Root Cause

The root cause of this vulnerability lies in insufficient bounds checking within the rtsp_parse_method function. The function does not adequately validate the length of input data before copying or processing it into a fixed-size buffer. This is a classic memory safety issue where the absence of proper input length validation allows buffer boundaries to be exceeded.

Attack Vector

The attack requires local access to the system running the vulnerable librtsp library. An attacker would need to craft malicious RTSP method data that, when parsed by the rtsp_parse_method function, exceeds the expected buffer boundaries. This could be achieved by:

1. Sending specially crafted RTSP requests to a local application using librtsp
2. Manipulating local configuration or data files that are processed by the vulnerable function
3. Exploiting inter-process communication channels that pass data to the parser

The vulnerability mechanism involves improper memory buffer boundary validation in the RTSP method parsing logic. When the rtsp_parse_method function receives input data, it fails to verify that the input length does not exceed the allocated buffer size before processing. Technical details and proof-of-concept information are available in the GitHub PoC Repository.

Detection Methods for CVE-2026-1110

Indicators of Compromise

• Unexpected crashes or segmentation faults in applications using librtsp
• Abnormal memory usage patterns in processes utilizing RTSP parsing functionality
• Core dumps or error logs indicating memory corruption in rtsp_parse_method
• Unusual local user activity targeting RTSP-enabled applications

Detection Strategies

• Deploy memory protection tools (ASAN, Valgrind) in development environments to detect buffer overflows during testing
• Implement runtime application self-protection (RASP) to monitor for memory corruption attempts
• Configure host-based intrusion detection systems (HIDS) to alert on abnormal process behavior
• Monitor application logs for crash patterns associated with RTSP parsing operations

Monitoring Recommendations

• Enable core dump analysis for applications using librtsp to capture exploitation attempts
• Implement file integrity monitoring on librtsp library files to detect unauthorized modifications
• Configure security information and event management (SIEM) rules to correlate crashes with potential exploitation attempts
• Monitor system calls from processes using librtsp for anomalous memory operations

How to Mitigate CVE-2026-1110

Immediate Actions Required

• Identify all systems and applications using the cijliu librtsp library
• Restrict local access to systems running vulnerable librtsp implementations
• Implement network segmentation to limit lateral movement if exploitation occurs
• Consider temporarily disabling or isolating RTSP functionality until a fix is available

Patch Information

No official patch is currently available from the vendor. The vendor was contacted about this disclosure but did not respond. Since librtsp uses continuous delivery with rolling releases, users should monitor the GitHub repository for any commits that address this buffer overflow issue.

For additional vulnerability intelligence, refer to VulDB #341702.

Workarounds

• Implement input validation at the application layer before passing data to librtsp functions
• Compile applications using librtsp with stack canaries and address space layout randomization (ASLR) enabled
• Use memory-safe wrappers around the rtsp_parse_method function to enforce input length limits
• Consider using alternative RTSP parsing libraries with better security track records until a fix is available

# Configuration example - Compile with security hardening flags
gcc -fstack-protector-strong -D_FORTIFY_SOURCE=2 -pie -fPIE -Wl,-z,relro,-z,now your_app.c -lrtsp -o your_app

# Enable ASLR system-wide (Linux)
echo 2 | sudo tee /proc/sys/kernel/randomize_va_space