Cyber Resilience

CVE-2026-35633

MediumPublic PoC

Published: 09 April 2026

Published
09 April 2026
Modified
15 April 2026
KEV Added
Patch
CVSS Score v4 6.9 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/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 0.0016 36.2th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-35633 is a medium-severity Memory Allocation with Excessive Size Value (CWE-789) vulnerability in Openclaw Openclaw. Its CVSS base score is 6.9 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 36.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

OpenClaw before 2026.3.22 contains an unbounded memory allocation vulnerability in remote media HTTP error handling that allows attackers to trigger excessive memory consumption. Attackers can send crafted HTTP error responses with large bodies to remote media endpoints, causing the application…

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to allocate unbounded memory before failure handling occurs.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

Unbounded memory allocation in HTTP response handling directly enables application-level resource exhaustion DoS via crafted inputs.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

Affected Assets

openclaw
openclaw
≤ 2026.3.22

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-770

This control implements explicit throttling on session allocation, addressing the weakness of allocating resources without limits.

addresses: CWE-770

Plan testing exercises resource allocation limits and throttling during simulated failures, directly addressing weaknesses that allow unbounded resource use.

addresses: CWE-770

Contingency plan updates ensure recovery strategies address unbounded resource allocation, making it harder for attackers to exploit lack of throttling to cause prolonged outages.

addresses: CWE-770

Provides continuity when unbounded resource allocation at the primary site leads to exhaustion and downtime.

addresses: CWE-770

Alternate services allow operations to continue when primary allocation of resources lacks limits or throttling.

addresses: CWE-770

Explicit planning of security-related actions requires defining limits, windows, and resource allocations, making allocation without throttling far less likely.

addresses: CWE-770

Measures of performance include tracking allocation behavior and throttling effectiveness, reducing the window for resource exhaustion attacks.

addresses: CWE-770

Imposes an inactivity-based limit on network resource allocation, throttling the number of concurrently held connections.

References