CVE-2022-46280

Executive Summary

CVE-2022-46280 is a critical use-of-uninitialized-pointer vulnerability in Open Babel 3.1.1 and master commit 530dbfa3, specifically within the PQS file format parsing functionality. An attacker can exploit this flaw by delivering a specially crafted malformed PQS file to a target, leading to arbitrary code execution with the privileges of the application parsing the file. With a CVSS score of 9.8, this vulnerability poses a severe risk to any organization using Open Babel to process untrusted chemical data files, particularly in automated pipeline environments where file input is not manually vetted.

The vulnerability is currently unpatched, with zero patch confidence from any tracked source, and no CISA KEV listing or public exploit code has been identified at the time of writing. This makes proactive detection and mitigation strategies essential for affected organizations until a vendor fix is released.

Technical Analysis

The vulnerability resides in the PQS format parsing functionality (pFormat) of Open Babel, a widely used open-source cheminformatics toolbox that converts chemical file formats. The root cause is a use of uninitialized pointer (CWE-824), where the parser fails to properly initialize a pointer variable before it is dereferenced during the processing of a PQS file.

Mechanism: When Open Babel processes a PQS-format file, the parser reads structured data into memory. If the file is malformed—for instance, missing certain required fields, containing truncated records, or supplying unexpected data types—the parser may attempt to dereference a pointer that was never assigned a valid memory address. This results in undefined behavior, which an attacker can leverage to redirect execution flow.

Attack Surface: The attack surface is any application or service that uses Open Babel to parse untrusted PQS files. This includes:

• Chemistry research platforms that accept user-uploaded molecule files.
• Automated data-processing pipelines in pharmaceutical, biotech, and academic environments.
• Web services that convert chemical data formats on the backend.
• Desktop GUI tools that allow opening of chemical structure files.

Technical Detail Constraints: The NVD description provides minimal technical specifics beyond the affected function (pFormat) and version information. No class names, specific function call chains, or exact memory layout details are available. The vulnerability class (uninitialized pointer) suggests a common pattern: a pointer variable declared but not initialized on all code paths, followed by a conditional path that dereferences it without prior assignment. Attackers typically exploit this by crafting input that triggers the uninitialized path and then controlling the value subsequently written to or read from the pointer.

Exploitation Scenarios

The attack chain is inferred from the vulnerability class and the NVD description. No public PoC exists, and the exact memory corruption mechanics are unknown.

1) Reconnaissance / Target Identification:
An attacker identifies organizations that use Open Babel for processing chemical data files. Targets include pharmaceutical R&D departments, academic chemistry labs, chemical database web services, and any platform offering file conversion APIs. The attacker may probe for the presence of Open Babel by submitting valid PQS files and observing response times or error messages, or by banner grabbing on web-facing API endpoints.

2) Triggering the Flaw Class:
The attacker crafts a malformed PQS file designed to exploit the uninitialized pointer. The file is structured to cause the parser to take a code path where a pointer variable is not initialized before use. This can be achieved by omitting mandatory header fields, inserting unexpected record types, or providing inconsistent data lengths. The file is delivered via email attachment, uploaded to a web service, or placed in a directory monitored by an automated processing script.

3) Payload Execution:
Upon parsing, the uninitialized pointer is dereferenced, and the value read from or written to the invalid memory address is controlled by the attacker through the file's content. This can be leveraged for arbitrary code execution by:

• Overwriting a function pointer with the address of attacker-controlled shellcode.
• Corrupting a virtual table pointer to redirect execution to attacker-injected code.
• Writing to a freed or invalid heap region to achieve arbitrary write primitives.

The exact payload construction depends on the memory layout of the Open Babel binary and the operating system, but typical shellcode would spawn a reverse shell, download a second-stage payload, or add a privileged user.

4) Post-Exploitation Impact:
Successful exploitation grants the attacker code execution with the privileges of the Open Babel process. In server environments, this often equates to the service account, potentially allowing lateral movement, data exfiltration of proprietary chemical data, or installation of persistent backdoors. In desktop environments, exploitation compromises the user's account and machine. Given the criticality (CVSS 9.8) and the lack of authentication requirements per the CVSS vector, exploitation is remote and unauthenticated if the parsing service is exposed to the network.

Impact Assessment

Business Impact: A CVSS score of 9.8 places this vulnerability in the critical severity range, indicating complete compromise of confidentiality, integrity, and availability. For organizations in the chemical, pharmaceutical, and biotechnology sectors, the impact is compounded by the sensitive nature of the data processed—proprietary molecular structures, drug candidates, and research data. An attacker who achieves arbitrary code execution could steal intellectual property, manipulate research data, or render systems inoperable.

Affected Systems: All deployments of Open Babel 3.1.1 and master commit 530dbfa3 are affected. The library is integrated into numerous downstream applications, including:

• Molecular visualization tools (e.g., PyMOL, Avogadro when using Open Babel backends).
• Batch conversion utilities and command-line tools.
• Web services and APIs for chemical data processing.
• Research pipeline systems that ingest user-submitted files.

Blast Radius: The lack of a patch means any system with Open Babel installed is vulnerable indefinitely. Even if no known exploitation has occurred, the vulnerability is trivially discoverable through fuzzing, and the widespread use of Open Babel in scientific computing expands the attack surface. The CNA-reported EPSS score of 0.00828 (54.1st percentile) suggests low immediate exploitation likelihood but significant potential as PoC becomes available. The "unpatched" status elevates the strategic risk, as defenders have no vendor-provided remediation.

Detection Guidance

Given the absence of a patch and the file-based attack vector, detection should focus on anomalous file submissions, process behavior, and network indicators. The following rules target the exploitation attempt and post-exploitation behavior.

Sigma Rule

The Sigma rule detects suspicious Open Babel process spawns or file access patterns, focusing on process creation anomalies and abnormal memory-access-related crash signatures in Windows environments.

title: Open Babel PQS Parser Uninitialized Pointer Exploitation Attempt
status: experimental
description: Detects potential exploitation of CVE-2022-46280 via malformed PQS file processing in Open Babel
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2022-46280
author: Valters IT Threat Intelligence
date: 2025/03/15
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\obabel.exe'
            - '\babel.exe'
        CommandLine|contains:
            - '.pqs'
            - '--convert'
    condition: selection
level: high
falsepositives:
    - Legitimate batch conversion of PQS files
    - Automated chemical processing pipelines
---

### YARA Rule
This YARA rule identifies malformed PQS file patterns commonly associated with exploitation attempts, focusing on file structure anomalies.

```yaml
rule CVE_2022_46280_PQS_Malformed_File
{
    meta:
        author = "Valters IT Threat Intelligence"
        description = "Detects malformed PQS files that may exploit uninitialized pointer in Open Babel"
        date = "2025-03-15"
        cve = "CVE-2022-46280"
        score = 80
    strings:
        $pqs_header = "PQS" ascii nocase
        $pqs_end = "END" ascii nocase
        $short_line = /^[^\n]{0,5}$/m
        $long_line = /^.{200,}$/m
        $null_byte = { 00 00 00 00 }
    condition:
        uint32(0) == 0x535150   // "PQS" at file offset 0
        and (1 of them)
        and ($short_line or $long_line)   // unusual line lengths indicating truncation/fragmentation
        and filesize < 200KB   // typical malformed sample size
}

Suricata IDS Rule

Detects network delivery of suspicious PQS files, focusing on MIME types, file signatures, and payload characteristics.

alert http any any -> any any (msg:"CVE-2022-46280 - Potential Malformed PQS File Download";
    flow:established,to_client;
    file.magic:"PQS";
    file.size:<200000;
    content:"filename="; nocase;
    pcre:"/\.pqs$/Ui";
    classtype:attempted-admin;
    sid:10002308; rev:1;)

Elastic Detection

EQL query to detect process crashes or abnormal termination of Open Babel processes, which may indicate exploitation.

process where process.name == "obabel.exe" and
  (event.action == "process_terminated" and
   process.exit_code == 3221225477)  // STATUS_ACCESS_VIOLATION

Splunk SPL Query

Queries Windows Event logs and Sysmon for Open Babel process events, looking for crash signatures and unusual command lines.

index=windows source="WinEventLog:Security" OR index=windows source="WinEventLog:Application"
| where (EventCode=4688 AND New_Process_Name="*\\obabel.exe") OR (EventCode=1000 AND Image="*\\obabel.exe")
| search New_Process_CommandLine="*.pqs"
| table _time, computer, User, New_Process_Name, New_Process_CommandLine
| sort - _time

Wazuh OSSEC Rule

Wazuh rule observing for Open Babel process crashes and abnormal memory access events.

<group name="openbabel,">
  <rule id="100308" level="12">
    <decodedate>%Y-%m-%d %H:%M:%S</decodedate>
    <match>obabel.exe</match>
    <regex>STATUS_ACCESS_VIOLATION|0xc0000005</regex>
    <description>Open Babel process crash - possible CVE-2022-46280 exploitation</description>
    <group>windows,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch Status: Unpatched. No vendor fix exists, no patch evidence from any tracked source, and the vendor fix field is N/A. The affected versions remain vulnerable.

1) Immediate Mitigations (compensating controls):

• Input Validation: If Open Babel is used in a service that accepts files, implement strict file validation before passing to Open Babel:
  • Restrict allowed file extensions to only those required by the business.
  • Use a hardening library (e.g., python-magic for MIME validation) to reject files that do not match expected PQS structure.
  • Implement file size limits to reject abnormally small or large files.
• Sandboxing/Isolation: Run Open Babel processing in a sandboxed environment:
  • Use containers (Docker) with minimal privileges and no network access.
  • Alternatively, run Open Babel in a dedicated virtual machine with no access to sensitive data.
• Disable PQS Parsing if Not Required: If PQS format is not a core business requirement, consider disabling or removing the PQS parser module from the Open Babel build.
• Monitor for Anomalous Activity: Deploy the detection rules above to identify exploitation attempts, especially in environments that automatically process uploaded files.

2) Patch/Upgrade Steps:

• Currently, there is no patched version available. Monitor Open Babel's official website (openbabel.org) and GitHub repository for security advisories and release announcements.
• If a newer version becomes available (greater than 3.1.1 or a commit after 530dbfa3), upgrade immediately:
  • Check your package manager for updates (apt, yum, or brew on macOS).
  • For source builds, pull the latest from the master branch and rebuild.
• Until a fix is released, consider reverting to a version released before the flawed commit if functionality requirements allow (though this may introduce other vulnerabilities).

3) Long-Term Hardening:

• Adopt a Security-Focused Fork or Patch: Monitor community patches or third-party distributions that may backport fixes.
• Implement a File-Filtering Proxy: Deploy a security appliance or service that sanitizes incoming chemical files before they reach Open Babel.
• Regular Vulnerability Scanning: Incorporate Open Babel version checks into your vulnerability management program; rescan after any CVE update.
• Incident Response Preparation: Given that this is an unpatched critical vulnerability, prepare an incident response playbook for potential exploitation, including forensic triage of crashed processes.
• User Education: If Open Babel is used in a desktop environment, educate users about the risk of opening untrusted .pqs files.

References

1. NVD Entry: https://nvd.nist.gov/vuln/detail/CVE-2022-46280 — Official CVE record and description.
2. Open Babel Official Site: https://openbabel.org/ — Monitor for security advisories and version releases.
3. Open Babel GitHub Repository: https://github.com/openbabel/openbabel — Track source code changes, issue reports, and potential fix commits.
4. CWE-824 Reference: https://cwe.mitre.org/data/definitions/824.html — Detailed description of the use of uninitialized pointer weakness class.
5. CISA Known Exploited Vulnerabilities Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog — Confirmed as not listed (as of March 2025), but monitor for future additions.

Threat Actor Evidence: No known threat actor campaigns, exploit-in-the-wild usage, or public PoC have been identified at the time of this report. However, the criticality of the vulnerability and the unpatched status warrant high vigilance. The EPSS score of 0.00828 indicates moderate exploitation likelihood over the next 30 days, but this can increase rapidly if a public PoC emerges.