CVE-2026-53840 | OpenClaw before 2026.5.12 contains an information disclosure… | CVSS 7.1 HIGH

Description

OpenClaw before 2026.5.12 contains an information disclosure vulnerability in streamable-http MCP servers that forwards operator-configured custom headers during cross-origin redirects. Attackers controlling or compromising an MCP endpoint can redirect requests to exfiltrate sensitive headers like API keys or tenant-routing credentials to attacker-controlled origins.

Metadata

CVE ID: CVE-2026-53840
State: PUBLISHED
Assigner: VulnCheck
Reserved: 2026-06-10 21:19 UTC
Published: 2026-06-16 18:04 UTC
Last updated: 2026-06-16 18:51 UTC
Primary CWE: CWE-522
Insufficiently Protected Credentials
Vendor / Product: OpenClaw / OpenClaw
Sources: cve.org · NVD

Severity & Metrics

7.1 HIGH CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N

SSVC — CISA Coordinator

Exploitation: none
Automatable: no
Tech. Impact: partial

Affected products (1)

Vendor	Product	Platform	Versions
OpenClaw	OpenClaw	—	0 < 2026.5.12, 2026.5.12

Weakness (CWE)

CWE	Source	Description
CWE-522	cna	Insufficiently Protected Credentials

CVSS scores (2)

Score	Severity	Version	Source	Vector
7.1	HIGH	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
6.0	MEDIUM	4.0	cna	CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

References (2)

GitHub Security Advisory (GHSA-rjxq-qqhf-8hwh) https://github.com/openclaw/openclaw/security/advisories/GHSA-rjxq-qqhf-8hwh
VulnCheck Advisory: OpenClaw < 2026.5.12 - Custom Header Leakage via MCP Streamable HTTP Cross-Origin Redirects https://www.vulncheck.com/advisories/openclaw-custom-header-leakage-via-mcp-streamable-http-cross-origin-redirects