CVE-2026-30858: CVE-2026-30858: Server-Side Request Forgery via DNS Rebinding in Tencent WeKnora

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CVE-2026-30858: Server-Side Request Forgery via DNS Rebinding in Tencent WeKnora

Vulnerability ID: CVE-2026-30858
CVSS Score: 7.5
Published: 2026-03-06

Tencent WeKnora versions prior to 0.3.0 contain a critical Server-Side Request Forgery (SSRF) vulnerability due to incomplete DNS pinning in the web_fetch tool. This flaw allows an unauthenticated attacker to bypass URL validation via DNS rebinding and access restricted internal network resources.

TL;DR

Unauthenticated SSRF in WeKnora < 0.3.0 via DNS rebinding allows access to internal network resources. Fixed in 0.3.0.

⚠️ Exploit Status: POC

Technical Details

CWE ID: CWE-918
Attack Vector: Network
CVSS v3.1: 7.5 (High)
EPSS Score: 0.00075
Impact: Information Disclosure / SSRF
Exploit Status: Proof of Concept

Affected Systems

Tencent WeKnora web_fetch tool
internal/agent/tools/web_fetch.go
Tencent WeKnora: < 0.3.0 (Fixed in: 0.3.0)

Code Analysis

Commit: 2b3f76e

Fix SSRF via DNS Rebinding in web_fetch tool

Mitigation Strategies

Upgrade WeKnora to version 0.3.0 or higher.
Implement strict egress network filtering on the WeKnora host to block access to private CIDR blocks and cloud metadata APIs.
Isolate components that fetch external web content in restricted network namespaces.

Remediation Steps:

Verify current WeKnora version in deployment.
Pull the latest version (0.3.0 or later) from the official repository.
Deploy the updated application and monitor logs for application stability.
Validate the fix by attempting a simulated DNS rebinding attack against the updated instance.

References

Read the full report for CVE-2026-30858 on our website for more details including interactive diagrams and full exploit analysis.

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