Cyber Resilience

CVE-2026-41405

Openclaw ≤ 2026.3.31

Public PoC
Published
28 April 2026
Modified
30 April 2026
Patch / advisory
CVSS Score v4 8.7
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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 0.0048 39th percentile
Risk Priority 45 floored blend · peak EPSS

Summary

CVE-2026-41405 is a high-severity Incorrect Behavior Order: Early Amplification (CWE-408) vulnerability in Openclaw Openclaw. Its CVSS base score is 8.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Network Denial of Service (T1498); ranked at the 39th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-14 (Permitted Actions Without Identification or Authentication) and AC-3 (Access Enforcement) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-41405 is a resource exhaustion vulnerability in OpenClaw versions prior to 2026.3.31. The issue stems from the software parsing Microsoft Teams webhook request bodies before performing JWT validation, which allows attackers to trigger excessive resource consumption without authentication. This flaw, classified under CWE-408 (Incorrect Behavior Order: Early Validation), carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), highlighting its high-impact availability disruption potential over the network with low complexity.

Unauthenticated remote attackers can exploit this vulnerability by sending specially crafted malicious MS Teams webhook payloads to affected OpenClaw servers. By bypassing the authentication checks through premature parsing, attackers can cause the server to exhaust CPU or memory resources, leading to denial-of-service conditions that disrupt service availability for legitimate users.

Mitigation is addressed in OpenClaw version 2026.3.31 and later, as detailed in the project's GitHub security advisory (GHSA-p464-m8x6-vhv8) and the associated patch commit (3834d47099dd13c8244ed6de8b9ea9855c553623), which reorder validation to parse payloads only after JWT checks. Administrators should upgrade to the fixed version promptly, as noted in the VulnCheck advisory, and consider network-level filtering of unexpected webhook traffic in the interim.

EU & UK References

Vulnerability Data

OpenClaw before 2026.3.31 parses MS Teams webhook request bodies before performing JWT validation, allowing unauthenticated attackers to trigger resource exhaustion. Remote attackers can send malicious Teams webhook payloads to exhaust server resources by bypassing authentication checks.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1498 Network Denial of Service Impact
Adversaries may perform Network Denial of Service (DoS) attacks to degrade or block the availability of targeted resources to users.
T1498.002 Reflection Amplification Impact
Adversaries may attempt to cause a denial of service (DoS) by reflecting a high-volume of network traffic to a target.
T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.002 Service Exhaustion Flood Impact
Adversaries may target the different network services provided by systems to conduct a denial of service (DoS).
T1499.003 Application Exhaustion Flood Impact
Adversaries may target resource intensive features of applications to cause a denial of service (DoS), denying availability to those applications.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-41331Same product: Openclaw Openclaw
CVE-2026-41374Same product: Openclaw Openclaw
CVE-2026-35626Same product: Openclaw Openclaw
CVE-2026-35665Same product: Openclaw Openclaw
CVE-2026-28452Same product: Openclaw Openclaw
CVE-2026-32980Same product: Openclaw Openclaw
CVE-2026-28478Same product: Openclaw Openclaw
CVE-2026-41408Same product: Openclaw Openclaw
CVE-2026-32049Same product: Openclaw Openclaw
CVE-2026-41399Same product: Openclaw Openclaw

Affected Assets

openclaw
openclaw
≤ 2026.3.31

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

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

Mitigating Controls (NIST 800-53 r5) AI

Explicitly identifies and limits actions permitted without identification or authentication, directly stopping early expensive operations.

Access enforcement requires authorization checks before any operation, structurally blocking expensive actions prior to authentication.

Requires unique identification and authentication of users before associating privileges, preventing unauthenticated expensive work.

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

Enforcing authentication before operations directly blocks the early expensive action described by the CWE.

PR.AA-05 mostly match
prevents

Policy-driven authorization enforcement prevents costly actions prior to proper access 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.

prevents

Access control policies that enforce authentication before resource-intensive operations directly prevent early amplification.

degrades

Identity management ensures entities are identified and authenticated prior to performing expensive actions.

prevents

Access rights provisioning can restrict expensive operations until authorization is granted.

prevents

Privileged access rights limit who can perform costly actions but do not enforce authentication order.

prevents

Information access restriction mechanisms can block resource-intensive operations until authentication succeeds.

prevents

Secure authentication ensures identity verification occurs before expensive operations are allowed.

References