CVE-2023-51642
Deserialization in Alltena Allegra ≤ 7.5.1
Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:LSummary
CVE-2023-51642 is a medium-severity Deserialization of Untrusted Data (CWE-502) vulnerability in Alltena Allegra. Its CVSS base score is 6.3 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 33% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
Allegra contains a deserialization of untrusted data vulnerability in the loadFieldMatch method that permits remote code execution. The flaw stems from insufficient validation of user-supplied input, allowing an attacker to supply a malicious serialized object that is processed without proper checks. The issue affects installations of Allegra and carries a CVSS 3.1 base score of 6.3.
An authenticated attacker can register an account with sufficient privileges and then invoke the vulnerable method to achieve arbitrary code execution in the context of the LOCAL SERVICE account. The product’s built-in registration mechanism lowers the barrier for obtaining the required access level.
Vendor release notes for version 7.5.1 and the Zero Day Initiative advisory ZDI-24-105 address the issue and indicate that an update resolves the deserialization flaw. The associated EPSS score has remained flat at 0.0628 with no material increase since disclosure.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-56354
Vulnerability Data
Allegra loadFieldMatch Deserialization of Untrusted Data Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Allegra. Although authentication is required to exploit this vulnerability, product implements a registration mechanism that can be…
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used to create a user with a sufficient privilege level. The specific flaw exists within the loadFieldMatch method. The issue results from the lack of proper validation of user-supplied data, which can result in deserialization of untrusted data. An attacker can leverage this vulnerability to execute code in the context of LOCAL SERVICE. Was ZDI-CAN-22506.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation can uncover deserialization flaws before deployment.
Input validation directly stops deserialization of untrusted data by ensuring inputs are valid before processing.
Engineering principles such as safe deserialization and input sanitization structurally prevent the weakness from being introduced.
Integrity verification tools can detect malformed or tampered serialized data after the fact.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
PR.PS-02 addresses only post-deployment updates/patching and cannot prevent introduction of unsafe deserialization code, yet it can remediate some instances when the flaw exists in outdated libraries or components.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing includes validation of deserialization routines and the use of untrusted data, reducing the likelihood that unsafe object reconstruction will be deployed.
Requiring vetted libraries, regular updates and SAST before release reduces the likelihood that deserialization logic will accept and act on attacker-controlled serialized objects.
Regular scanning of third-party libraries and timely patching reduce the likelihood that unsafe deserialization vulnerabilities remain active.
Mandatory malware scanning of data received over networks or storage media intercepts malicious serialized payloads before they are deserialized by the target application.