CVE-2026-62212: Openclaw Race Condition Vulnerability

CVE-2026-62212 Overview

CVE-2026-62212 is a race condition vulnerability in OpenClaw versions before 2026.5.28. The flaw resides in the MS Teams safeFetch Domain Name System (DNS) rebinding check. When the affected feature is enabled and reachable, a lower-trust caller can win a timing window between DNS validation and use of the resolved address. This time-of-check to time-of-use (TOCTOU) condition [CWE-367] allows actions that should have required a stronger authorization or policy check. The practical impact depends on the operator's configuration and whether lower-trust input can reach the vulnerable code path.

Critical Impact
A network-adjacent attacker with low privileges can bypass the DNS rebinding safeguard in safeFetch, potentially reaching internal resources that policy checks were designed to protect.

Affected Products

OpenClaw (Node.js package) versions before 2026.5.28
Deployments with the MS Teams safeFetch feature enabled
Environments where lower-trust callers can reach the safeFetch code path

Discovery Timeline

2026-07-17 - CVE-2026-62212 published to the National Vulnerability Database (NVD)
2026-07-20 - Last updated in NVD database

Technical Details for CVE-2026-62212

Vulnerability Analysis

The vulnerability is a classic time-of-check to time-of-use (TOCTOU) race condition [CWE-367]. The safeFetch routine validates a hostname against DNS rebinding rules, then issues an outbound HTTP request using the same hostname. Between these two operations, DNS resolution can return a different address on subsequent lookups. An attacker controlling an authoritative DNS server can serve a legitimate external address during validation and a restricted internal address during fetch. This defeats the rebinding safeguard and permits requests the policy intended to block.

Root Cause

The check-then-use sequence in safeFetch performs DNS resolution twice without pinning the resolved address. The validation stage confirms the target is not an internal or reserved network range. The use stage re-resolves the hostname, opening a window for an attacker-controlled resolver to swap the answer. This design fails to enforce atomicity between validation and connection.

Attack Vector

Exploitation requires network access and low-privileged authenticated context on the calling side. The attacker registers a domain under their control and configures short time-to-live (TTL) DNS responses. During validation the resolver returns a public address. On the follow-up lookup for the actual fetch, the resolver returns a private or loopback address such as 169.254.169.254 or 127.0.0.1. The MS Teams safeFetch path then issues the request against an internal service, producing a server-side request forgery (SSRF) outcome tied to the race window.

No public proof-of-concept exploit is currently available. See the VulnCheck Authentication Bypass Advisory for further technical detail.

Detection Methods for CVE-2026-62212

Indicators of Compromise

Outbound DNS queries from OpenClaw hosts to domains with unusually short TTL values followed by connections to internal RFC1918 or link-local addresses
safeFetch request logs showing target hostnames that resolve to different IP addresses within seconds
Requests from the OpenClaw process to cloud metadata endpoints such as 169.254.169.254 or internal management interfaces

Detection Strategies

Correlate DNS resolver logs with application-level safeFetch request logs to identify divergent answers for the same hostname within a single request lifecycle
Alert on OpenClaw processes initiating connections to loopback, link-local, or private address ranges when the operator does not expect internal traffic
Review authentication and authorization audit trails for MS Teams integration paths reached without the expected policy checks

Monitoring Recommendations

Capture and retain DNS query and response telemetry from hosts running OpenClaw for at least 30 days
Instrument the safeFetch code path with logging that records both the validated address and the address actually used for the outbound request
Monitor egress firewall logs for OpenClaw-originated traffic that violates the intended destination policy

How to Mitigate CVE-2026-62212

Immediate Actions Required

Upgrade OpenClaw to version 2026.5.28 or later on all affected deployments
Inventory environments to confirm which instances expose the MS Teams safeFetch feature to lower-trust callers
Restrict network egress from OpenClaw hosts to only the destinations required for business function

Patch Information

The maintainers published a fix in OpenClaw 2026.5.28. Refer to the OpenClaw GitHub Security Advisory GHSA-wxm8-ghhq-q688 for the authoritative patch notes and upgrade guidance.

Workarounds

Disable the MS Teams safeFetch feature if it is not required for operations
Place OpenClaw behind an egress proxy that enforces destination allow-listing independent of DNS resolution
Block OpenClaw hosts from reaching internal management ranges, cloud metadata endpoints, and loopback interfaces at the network layer

bash

# Example egress restriction using iptables to block metadata and loopback abuse
iptables -A OUTPUT -m owner --uid-owner openclaw -d 169.254.169.254 -j REJECT
iptables -A OUTPUT -m owner --uid-owner openclaw -d 10.0.0.0/8 -j REJECT
iptables -A OUTPUT -m owner --uid-owner openclaw -d 172.16.0.0/12 -j REJECT
iptables -A OUTPUT -m owner --uid-owner openclaw -d 192.168.0.0/16 -j REJECT