Cyber Resilience

CVE-2026-102101

Deserialization in Accellion Kiteworks ≤ 9.5.0

Published
30 September 2026
Modified
07 October 2026
Patch / advisory
CVSS Score v3.1 8.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0031 21th percentile
Risk Priority 58 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-102101 is a high-severity Deserialization of Untrusted Data (CWE-502) vulnerability in Accellion Kiteworks. Its CVSS base score is 8.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked at the 21th percentile by exploit likelihood (below the median); 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 SA-8 (Security and Privacy Engineering Principles) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Kiteworks Core before version 9.5.0 is vulnerable to Deserialization of Untrusted Data. A deserialization weakness in Kiteworks Core could, under certain conditions, allow crafted data to be deserialized unsafely, potentially resulting in remote code execution on the appliance. Exploitation depends…

more

on an attacker first being able to influence the affected data, so this issue is not exploitable on its own.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-39636Shared CWE-502
CVE-2026-21655Shared CWE-502
CVE-2023-46279Shared CWE-502
CVE-2023-27068Shared CWE-502
CVE-2026-45794Shared CWE-502
CVE-2026-82222Shared CWE-502
CVE-2025-54001Shared CWE-502
CVE-2026-34659Shared CWE-502
CVE-2025-58592Shared CWE-502
CVE-2026-80513Shared CWE-502

Affected Assets

accellion
kiteworks
≤ 9.5.0

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can uncover deserialization flaws before deployment.

Engineering principles such as safe deserialization and input sanitization structurally prevent the weakness from being introduced.

Input validation directly stops deserialization of untrusted data by ensuring inputs are valid before processing.

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 none match
blocks

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.

removes
removes
removes
removes
removes

References