Cyber Resilience

CVE-2026-45021

Published
28 May 2026
Modified
17 June 2026
CVSS Score v4 5.1
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0020 11th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-45021 is a medium-severity Origin Validation Error (CWE-346) vulnerability. Its CVSS base score is 5.1 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique DHCP Spoofing (T1557.003); ranked at the 11th 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

Vulnerability Data

Kuma is a modern Envoy-based service mesh that can run on every cloud across both Kubernetes and VMs. Prior to 2.7.25, 2.9.15, 2.11.13, 2.12.10, and 2.13.5, the default kuma-cp config leaks the admin bootstrap token and signing keys to any…

more

webpage the operator visits while the control plane is reachable from their browser. CorsAllowedDomains: [".*"] reflects any Origin, and LocalhostIsAdmin: true promotes requests from 127.0.0.1 to mesh-system:admin. A cross-origin fetch() from a malicious page returns the admin JWT and signing material. This vulnerability is fixed in 2.7.25, 2.9.15, 2.11.13, 2.12.10, and 2.13.5.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1557.003 DHCP Spoofing Credential Access
Adversaries may redirect network traffic to adversary-owned systems by spoofing Dynamic Host Configuration Protocol (DHCP) traffic and acting as a malicious DHCP server on the victim network.
T1557 Adversary-in-the-Middle Credential Access
Adversaries may attempt to position themselves between two or more networked devices using an adversary-in-the-middle (AiTM) technique to support follow-on behaviors such as [Network Sniffing](https://attack.
T1557.001 Name Resolution Poisoning and SMB Relay Credential Access
By responding to LLMNR/NBT-NS/mDNS network traffic, adversaries may spoof an authoritative source for name resolution to force communication with an adversary controlled system.
T1557.002 ARP Cache Poisoning Credential Access
Adversaries may poison Address Resolution Protocol (ARP) caches to position themselves between the communication of two or more networked devices.
T1557.004 Evil Twin Credential Access
Adversaries may host seemingly genuine Wi-Fi access points to deceive users into connecting to malicious networks as a way of supporting follow-on behaviors such as [Network Sniffing](https://attack.
T1189 Drive-by Compromise Initial Access
Adversaries may gain access to a system through a user visiting a website over the normal course of browsing.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-7581Shared CWE-346, CWE-942
CVE-2024-25124Shared CWE-346, CWE-942
CVE-2025-4839Shared CWE-346, CWE-942
CVE-2026-7643Shared CWE-346, CWE-942
CVE-2026-6143Shared CWE-346, CWE-942
CVE-2025-11304Shared CWE-346, CWE-942
CVE-2025-1083Shared CWE-346, CWE-942
CVE-2025-4542Shared CWE-346, CWE-942
CVE-2026-44184Shared CWE-346, CWE-942
CVE-2026-27579Shared CWE-346, CWE-942

Affected Assets

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 1 OS baseline
Validate
Prove the fix (OWASP ASVS)
  • V3.4.3
  • V3.4.6
  • V3.5.2

Mitigating Controls (NIST 800-53 r5) AI

Information flow enforcement directly requires validating the source of data before allowing transmission or receipt.

Device identification and authentication mandates verifying the source before establishing connections.

Session authenticity mechanisms require validation that communications originate from the expected party.

Boundary protection at interfaces enforces checks on the origin of incoming communications.

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.AA-03 mostly match
prevents

Authentication directly verifies the source of users/services/hardware, mitigating origin validation failures.

PR.AA-04 mostly match
prevents

Verifying identity assertions enforces origin validation for conveyed claims.

PR.PS-01 mostly match
prevents

Hardened configuration baselines and reviews directly prevent permissive CSP or cross-domain policies.

PR.PS-06 mostly match
prevents

Secure SDLC activities include review and testing of web security policies to avoid untrusted domains.

ID.AM-03 partial match
prevents

Documenting authorized flows supports origin validation by defining expected sources.

ID.RA-01 partial match
prevents

Vulnerability identification processes can surface permissive policy misconfigurations.

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 can detect overly permissive cross-domain policies but does not prevent their initial introduction.

mitigates

Network security controls enforce origin validation at network boundaries.

mitigates

Security of network services includes validating the authenticity of service endpoints.

mitigates

Network segregation reduces exposure but does not directly validate origins.

degrades

Web filtering can block untrusted domains at the network level, partially mitigating permissive cross-domain policies.

prevents

Application security requirements explicitly call for origin validation of inputs and communications.

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).

Oracle Linux 8 (3 rules)
  • V-248574 YUM must be configured to prevent the installation of patches, service packs, device drivers, or OL 8 system components that have not been digitally signed using a certificate that is recognized and approved by the organization. prevents CWE-346
  • V-248575 OL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. prevents CWE-346
  • V-248827 OL 8 must not have the rsh-server package installed. prevents CWE-346

References