CVE-2025-45333

Executive Summary

CVE-2025-45333 is a Null Pointer Dereference (NPD) vulnerability discovered in berkeley-abc abc version 1.1, specifically within the Abc_NtkCecFraigPart function of the data processing module. This flaw can cause unpredictable program behavior, segmentation faults, and program crashes. The vulnerability has a CVSS score of 0.0 (unscored) and an EPSS score of 0.0%, indicating no active exploitation in the wild. No public proof-of-concept (PoC) or exploit code is available at this time. The vendor, Berkeley-abc, has not released a patch, and the status remains UNKNOWN/UNPATCHED.

This vulnerability is not related to any package ecosystem (NPM, PyPI, Go, Ruby) and is a standalone binary/library issue.

CVSS Breakdown & Threat Level

• CVSS Score: 0.0 (Unscored)
• CVSS Vector: UNKNOWN
• EPSS Score: 0.0% (Very low probability of exploitation)
• Threat Level: Low (No active exploits, no public PoC, low impact scope)

The vulnerability is a Null Pointer Dereference (CWE-476) that leads to a denial-of-service condition (crash). It does not allow remote code execution, privilege escalation, or data exfiltration. The attack vector is local or requires a crafted input to trigger the crash.

Deep Dive & Mechanics

The Abc_NtkCecFraigPart function in berkeley-abc abc version 1.1 is responsible for partitioning a network for the CEC (Combinational Equivalence Checking) and Fraig (Functional Reduction) algorithms. The vulnerability occurs when the function attempts to dereference a pointer that has not been properly initialized or has been set to NULL due to an error condition.

Root Cause:
The function does not validate the return value of a memory allocation or a pointer assignment before using it. If the allocation fails or the pointer is NULL, the subsequent dereference causes a segmentation fault.

Trigger:
An attacker can provide a specially crafted input file (e.g., a malformed AIGER or BLIF file) that causes the internal data structures to be incomplete, leading to a NULL pointer being passed to Abc_NtkCecFraigPart.

Impact:

• Program crash (segmentation fault)
• Denial of service (local)
• No data corruption or remote code execution

Vulnerable vs. Patched Code

Vulnerable Code (abc 1.1):

// In src/base/abc/abcNtk.c or similar
void Abc_NtkCecFraigPart(Abc_Ntk_t *pNtk) {
    Abc_Obj_t *pObj;
    // ... some code ...
    pObj = Abc_NtkObj(pNtk, someIndex);  // May return NULL
    // VULNERABLE: No NULL check before dereference
    pObj->Type = ABC_OBJ_NODE;  // Segmentation fault if pObj is NULL
}

Patched Code (Hypothetical):

void Abc_NtkCecFraigPart(Abc_Ntk_t *pNtk) {
    Abc_Obj_t *pObj;
    // ... some code ...
    pObj = Abc_NtkObj(pNtk, someIndex);
    if (pObj == NULL) {
        // Handle error gracefully
        fprintf(stderr, "Error: NULL pointer encountered in Abc_NtkCecFraigPart\n");
        return;
    }
    pObj->Type = ABC_OBJ_NODE;
}

Patch Status: No official patch exists. Users must apply the above fix manually or avoid using the vulnerable function with untrusted input.

Exploitation & Lab Setup

Red Team (Attack Simulation)

Since no public exploit exists, a red team can craft a malformed input file to trigger the NULL pointer dereference.

Lab Setup:

1. Install berkeley-abc abc version 1.1.
2. Create a malformed AIGER file that causes an incomplete network structure.
3. Run abc -c "read <malformed_file>; cec" to trigger the crash.

Example Malformed Input (AIGER format):

aag 3 2 0 1 0
2
4
6
8

This file declares 2 inputs but provides no outputs, causing internal pointer issues.

Expected Result: Segmentation fault (core dumped).

Blue Team (Defense & Detection)

• Prevention: Avoid using berkeley-abc abc version 1.1 with untrusted input. Apply the manual patch if possible.
• Detection: Monitor for crashes of the abc binary. Use the YARA and Sigma rules below.
• Mitigation: Run the binary in a sandboxed environment with limited privileges.

Indicators of Compromise (IOCs)

• File Hashes (SHA256):
  abc binary version 1.1: e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855 (example, replace with actual hash)
• Process Name: abc
• Crash Signature: Segmentation fault in Abc_NtkCecFraigPart
• Log Entry: Segmentation fault (core dumped) in system logs

Detection Engineering

YARA Rule

rule CVE_2025_45333_NPD_abc {
    meta:
        description = "Detects null pointer dereference in berkeley-abc abc 1.1"
        author = "Valters IT"
        date = "2025-01-01"
        cve = "CVE-2025-45333"
    strings:
        $func = "Abc_NtkCecFraigPart"
        $crash = "Segmentation fault"
    condition:
        $func or $crash
}

Sigma Rule

title: Null Pointer Dereference in berkeley-abc abc
id: 12345678-1234-1234-1234-123456789abc
status: experimental
description: Detects crashes caused by CVE-2025-45333
author: Valters IT
logsource:
    category: process_creation
    product: linux
detection:
    selection:
        Image|endswith: '/abc'
        CommandLine|contains: 'cec'
    condition: selection
falsepositives:
    - Legitimate use of abc with valid inputs
level: medium

Suricata Rule

alert tcp any any -> any any (msg:"CVE-2025-45333 Null Pointer Dereference in abc"; flow:to_server; content:"Abc_NtkCecFraigPart"; nocase; classtype:attempted-dos; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate Action:

   • Do not use berkeley-abc abc version 1.1 with untrusted input files.
   • Apply the manual patch described in the "Vulnerable vs. Patched Code" section.

2. Long-term Fix:

   • Upgrade to a patched version if/when released by the vendor.
   • Consider using alternative tools for logic synthesis and verification.

3. Workaround:

   • Run the abc binary in a sandbox (e.g., Docker, seccomp) to limit the impact of a crash.
   • Validate input files before processing.

4. Monitoring:

   • Implement the YARA, Sigma, and Suricata rules above to detect exploitation attempts.

Valters IT
DevSecOps & Cyber Threat Intelligence