Cyber Resilience

CVE-2026-23635

Accellion Kiteworks ≤ 9.2.1

Published
25 March 2026
Modified
27 March 2026
Patch / advisory
View advisory
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
EPSS Score 0.0032 24th percentile
Risk Priority 49 floored blend · peak EPSS

Summary

CVE-2026-23635 is a medium-severity Unprotected Transport of Credentials (CWE-523) vulnerability in Accellion Kiteworks. Its CVSS base score is 6.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Network Sniffing (T1040); ranked at the 24th 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 SC-8 (Transmission Confidentiality and Integrity) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A04:2025 Cryptographic Failures

EU & UK References

Vulnerability Data

Kiteworks is a private data network (PDN). In Kiteworks Secure Data Forms prior to version 9.2.1, a misconfiguration of the security attributes could potentially lead to Unprotected Transport of Credentials under certain circumstances. Upgrade Kiteworks to version 9.2.1 or later…

more

to receive a patch.

CWE(s)
CWE-523

Related Threats

MITRE ATT&CK Enterprise Techniques

T1040 Network Sniffing Credential Access
Adversaries may passively sniff network traffic to capture information about an environment, including authentication material passed over the network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-29092Same product: Accellion Kiteworks
CVE-2026-24782Same product: Accellion Kiteworks
CVE-2026-24752Same product: Accellion Kiteworks
CVE-2026-28271Same product: Accellion Kiteworks
CVE-2026-28269Same product: Accellion Kiteworks
CVE-2026-23514Same product: Accellion Kiteworks
CVE-2026-24753Same product: Accellion Kiteworks
CVE-2025-53939Same product: Accellion Kiteworks
CVE-2026-23636Same product: Accellion Kiteworks
CVE-2026-24750Same product: Accellion Kiteworks

Affected Assets

accellion
kiteworks
≤ 9.2.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

—

Mitigating Controls (NIST 800-53 r5) AI

SC-8 Transmission Confidentiality and Integrity good match

SC-8 requires confidentiality protection for transmitted data, directly stopping credentials from traveling in plaintext.

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.DS-02 full match
prevents

Encryption of data-in-transit directly prevents exposure of credentials during login.

PR.AA-04 mostly match
prevents

Protecting identity assertions in transit covers credential transport but is narrower than the full control scope.

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.

A.8.24 Use of cryptography mostly match
prevents

Requires use of cryptography, directly enabling encryption of credentials in transit.

A.5.14 Information transfer partial match
prevents

Requires secure information transfer, which can include protecting credentials in transit.

A.5.17 Authentication information partial match
degrades

Addresses management of authentication information, indirectly supporting protection during transmission.

A.8.20 Networks security partial match
prevents

Requires network security controls that can protect credential transmission.

A.8.21 Security of network services partial match
prevents

Addresses security of network services, which may include protecting authentication traffic.

A.8.26 Application security requirements partial match
prevents

Specifies application security requirements that can include secure credential transmission.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

RHEL 8 (2 rules)
  • V-230487 RHEL 8 must not have the telnet-server package installed. prevents CWE-523
  • V-230492 RHEL 8 must not have the rsh-server package installed. prevents CWE-523

References