Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:NSummary
CVE-2026-28271 is a medium-severity Reliance on Reverse DNS Resolution for a Security-Critical Action (CWE-350) vulnerability in Accellion Kiteworks. Its CVSS base score is 6.5 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 36th 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 AC-4 (Information Flow Enforcement) and IA-3 (Device Identification and Authentication) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-9066
Vulnerability Data
Kiteworks is a private data network (PDN). Prior to version 9.2.0, a vulnerability in Kiteworks configuration functionality allows bypassing of SSRF protections through DNS rebinding attacks. Malicious administrators could exploit this to access internal services that should be restricted. Version…
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9.2.0 contains a patch for the issue.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.3.6V1.5.3V5.3.2V10.4.7
Mitigating Controls (NIST 800-53 r5) AI
Information flow enforcement can restrict which destinations the server is allowed to contact on behalf of users.
Requiring unique device identification and authentication before any connection prevents security decisions based solely on unverified reverse DNS lookups.
Mandating data-origin authentication for name/address resolution stops reliance on unauthenticated reverse DNS responses.
Input validation directly stops untrusted URLs from being accepted and fetched without destination checks.
Boundary protection limits the network reach of server-initiated requests even if SSRF 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.
Strong authentication of users/services/hardware directly prevents security decisions based on unauthenticated reverse DNS.
Secure development practices directly include input validation and destination allow-listing that prevent SSRF.
Monitoring DNS services can detect adverse events stemming from unverified reverse lookups.
Runtime monitoring of web applications and services can detect anomalous outbound requests indicative of SSRF.
Vulnerability identification processes can discover and record SSRF flaws in web applications.
Network protections reduce the feasibility of attackers exploiting unauthenticated reverse-DNS decisions.
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.
Operational threat data describing SSRF campaigns can be used to tighten outbound-request allow-lists and detection rules before attackers exploit them.
Network security controls can enforce authenticated, non-DNS-based host identification.
Secure network services discourage use of unauthenticated reverse-DNS for access decisions.
Application security requirements can mandate authenticated host verification instead of reverse DNS.
Secure architecture principles discourage reliance on unauthenticated DNS for security decisions.
Secure coding practices can replace reverse-DNS checks with cryptographically verified identities.