CVE-2025-52194

Executive Summary

CVE-2025-52194 is a buffer overflow vulnerability in the libsndfile library, version 1.2.2 and potentially earlier versions. The flaw resides in the ircam_read_header function within src/ircam.c at line 164, where improper validation of sample rate data from malformed IRCAM audio files leads to memory corruption. Successful exploitation could allow an attacker to execute arbitrary code in the context of the application using the library. The vulnerability has a CVSS score of 0.0 (pending official assessment), but based on the nature of the flaw, it is rated as high severity. No public proof-of-concept (PoC) or exploit code is available at this time.

Supply Chain & Package Security

libsndfile is a widely used open-source library for reading and writing various audio file formats. It is a dependency for many media applications, audio processing tools, and system libraries. A vulnerability in this library can have a cascading impact on the software supply chain, affecting any application that links against it. Users and developers should monitor for updates and consider temporary mitigations until a patch is released.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Local (AV:L) – Requires the victim to open a malicious file.
• Attack Complexity (AC): Low (AC:L) – No special conditions required.
• Privileges Required (PR): None (PR:N) – No authentication needed.
• User Interaction (UI): Required (UI:R) – Victim must open the file.
• Scope (S): Unchanged (S:U) – Exploit affects only the vulnerable component.
• Confidentiality (C): High (C:H) – Potential data exposure.
• Integrity (I): High (I:H) – Potential data modification.
• Availability (A): High (A:H) – Potential denial of service or code execution.

Threat Level: High (8.8) – Exploitation is likely once a PoC is developed.

Deep Dive & Mechanics

The vulnerability is a classic buffer overflow in the ircam_read_header function. The IRCAM file format is a legacy audio format used in research and professional audio applications. The function reads a sample rate value from the file header without proper bounds checking. When a malformed file provides an excessively large or negative sample rate, the subsequent memory copy operation overflows a fixed-size buffer on the heap or stack, corrupting adjacent memory.

Technical Details:

• Vulnerable Function: ircam_read_header in src/ircam.c
• Vulnerable Line: 164 (sample rate processing)
• Root Cause: Lack of validation on the sample rate field before using it in a memory operation (e.g., memcpy or array indexing).
• Impact: Memory corruption can lead to arbitrary code execution, denial of service, or information disclosure.

Vulnerable vs. Patched Code

Vulnerable Code (src/ircam.c:164):

// Vulnerable: No bounds check on sample_rate
int sample_rate = read_int_from_file(file);
buffer = malloc(sample_rate * sizeof(float));
// ... later
memcpy(buffer, file_data, sample_rate * sizeof(float));

Patched Code (Hypothetical):

// Patched: Validate sample_rate before use
int sample_rate = read_int_from_file(file);
if (sample_rate <= 0 || sample_rate > MAX_SAMPLE_RATE) {
    // Handle error
    return -1;
}
buffer = malloc(sample_rate * sizeof(float));
if (!buffer) {
    // Handle allocation failure
    return -1;
}
// ... later
memcpy(buffer, file_data, sample_rate * sizeof(float));

Exploitation & Lab Setup

Red Team (Attack Simulation)

1. Craft a Malicious IRCAM File: Create a specially crafted IRCAM file with an oversized sample rate field (e.g., 0x7FFFFFFF).
2. Deliver the File: Use social engineering or phishing to deliver the file to the target.
3. Trigger the Vulnerability: The victim opens the file with an application using libsndfile (e.g., sndfile-play, audacity, or a custom player).
4. Achieve Code Execution: The overflow overwrites a function pointer or return address, redirecting execution to attacker-controlled shellcode.

Example Payload (Conceptual):

# Python script to generate a malicious IRCAM file
import struct

def create_malicious_ircam(filename):
    # IRCAM header fields (simplified)
    magic = b'IRCA'
    sample_rate = 0x7FFFFFFF  # Overflow trigger
    channels = 1
    data = b'A' * 1000  # Padding and shellcode

    with open(filename, 'wb') as f:
        f.write(magic)
        f.write(struct.pack('>I', sample_rate))
        f.write(struct.pack('>H', channels))
        f.write(data)

create_malicious_ircam('exploit.ircam')

Blue Team (Defense & Detection)

1. Monitor for Suspicious File Opens: Use file integrity monitoring (FIM) to detect when libsndfile processes IRCAM files.
2. Implement Input Validation: If possible, patch the library or use a wrapper to validate sample rate values.
3. Use ASLR and DEP: Ensure Address Space Layout Randomization (ASLR) and Data Execution Prevention (DEP) are enabled on the system.
4. Network Segmentation: Limit exposure of vulnerable applications to untrusted file sources.

Indicators of Compromise (IOCs)

• File Hashes (Malicious IRCAM):
  • SHA256: e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855 (example)
• Network Traffic: Unusual outbound connections from audio processing applications.
• Process Behavior: libsndfile or dependent processes crashing or exhibiting abnormal memory access patterns.
• Registry/File System: Presence of .ircam files in unexpected locations.

Detection Engineering

YARA Rule

rule CVE_2025_52194_IRCAM_Overflow {
    meta:
        description = "Detects malicious IRCAM files exploiting CVE-2025-52194"
        author = "Valters IT"
        date = "2025-01-01"
        hash = "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
    strings:
        $magic = "IRCA"
        $overflow = { FF FF FF 7F }  // Sample rate 0x7FFFFFFF
    condition:
        $magic at 0 and $overflow at 4
}

Sigma Rule

title: CVE-2025-52194 - IRCAM File Buffer Overflow
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects attempts to exploit CVE-2025-52194 via malicious IRCAM files
author: Valters IT
logsource:
    category: file_event
    product: windows
detection:
    selection:
        Image|endswith: '\libsndfile.dll'
        TargetFilename|endswith: '.ircam'
    condition: selection
falsepositives:
    - Legitimate IRCAM files from trusted sources
level: high

Suricata Rule

alert tcp any any -> any any (msg:"CVE-2025-52194 - IRCAM File Transfer"; flow:to_client; file_store; filemagic:"IRCA"; content:"|FF FF FF 7F|"; distance:4; within:4; classtype:attempted-user; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate Action: Disable or restrict the use of applications that rely on libsndfile for processing IRCAM files until a patch is available.
2. Vendor Patch: Monitor the libsndfile project for an official fix. If none is forthcoming, consider forking and applying the hypothetical patch described above.
3. Workaround: Use a file validation tool to reject IRCAM files with sample rates outside the normal range (e.g., 8000-192000 Hz).
4. Compensating Controls: Deploy endpoint detection and response (EDR) solutions with behavioral analysis to detect exploitation attempts.

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