Cyber Resilience

CVE-2023-26436

Deserialization in Open-Xchange Appsuite Backend ≤ 7.10.6

Public PoCDeserialization
Published
20 June 2023
Modified
21 November 2024
CVSS Score v3.1 7.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.013 67th percentile
Risk Priority 54 floored blend · peak EPSS

Summary

CVE-2023-26436 is a high-severity Code Injection (CWE-94) vulnerability in Open-Xchange Open-Xchange Appsuite Backend. Its CVSS base score is 7.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 33% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Attackers with access to the "documentconverterws" API were able to inject serialized Java objects, that were not properly checked during deserialization. Access to this API endpoint is restricted to local networks by default. Arbitrary code could be injected that is…

more

being executed when processing the request. A check has been introduced to restrict processing of legal and expected classes for this API. We now log a warning in case there are attempts to inject illegal classes. No publicly available exploits are known.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
T1059.002 AppleScript Execution
Adversaries may abuse AppleScript for execution.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1059.005 Visual Basic Execution
Adversaries may abuse Visual Basic (VB) for execution.
T1059.006 Python Execution
Adversaries may abuse Python commands and scripts for execution.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-10382Shared CWE-502, CWE-94
CVE-2025-51427Shared CWE-502, CWE-94
CVE-2025-57773Shared CWE-502, CWE-94
CVE-2026-11860Shared CWE-502, CWE-94
CVE-2026-58025Shared CWE-502, CWE-94
CVE-2025-53002Shared CWE-502, CWE-94
CVE-2021-29505Shared CWE-502, CWE-94
CVE-2025-69872Shared CWE-502, CWE-94
CVE-2026-31253Shared CWE-502, CWE-94
CVE-2023-44392Shared CWE-502, CWE-94

Affected Assets

open-xchange
open-xchange appsuite backend
7.10.6 · ≤ 7.10.6

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.3.1

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-502 CWE-94

Untrusted serialized data can be deserialized and observed inside the chamber, blocking gadget-chain exploitation outside the sandbox.

addresses: CWE-94 CWE-502

Validates inputs used in dynamic code generation to block injected directives.

addresses: CWE-502

Penetration testing supplies malicious serialized objects, detecting unsafe deserialization and supporting corrective actions.

addresses: CWE-502

Evaluation of untrusted data handling (deserialization testing) reveals unsafe processing, which the required remediation process addresses.

addresses: CWE-94

Makes persistent code injection into loaded programs impossible when the executable image itself resides on hardware-protected read-only media.

addresses: CWE-94

Directly prevents execution of attacker-supplied code written into data memory regions.

addresses: CWE-502

Identifies and blocks malicious code introduced through deserialization of untrusted data at system boundaries.

addresses: CWE-502

Integrity verification of serialized information can detect tampering before deserialization occurs.

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-06 mostly match
prevents

PR.PS-06's SDLC practices directly target injection flaws via secure coding and testing (mostly), yet as a single broad outcome it leaves many code-generation specifics unaddressed (partial).

PR.DS-10 none match
prevents

PR.DS-10 protects runtime data confidentiality/integrity but has no bearing on neutralizing externally influenced input during code generation, so neither direction shows any preventive effect.

PR.PS-02 none match
prevents

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.

finds

Security testing includes validation of deserialization routines and the use of untrusted data, reducing the likelihood that unsafe object reconstruction will be deployed.

prevents

Banning unapproved code samples and unauthenticated web services, combined with secure-coding standards and SAST, prevents the dynamic generation or inclusion of attacker-supplied code.

finds

Regular scanning of third-party libraries and timely patching reduce the likelihood that unsafe deserialization vulnerabilities remain active.

none

Controls that restrict unauthorized or malicious code from being introduced via external networks or removable media limit opportunities for an attacker to inject and execute arbitrary code.

References