WeKnora has DNS Rebinding Vulnerability in web_fetch Tool that Allows SSRF to Internal Resources

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

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

EPSS

• CVE-2026-30858: 0.41% estimated exploitation activity in the next 30 days; percentile 35.07 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary A DNS rebinding vulnerability in the webfetch tool allows an unauthenticated attacker to bypass URL validation and access internal resources on the server, including private IP addresses (e.g., 127.0.0.1, 192.168.x.x). By crafting a malicious domain that resolves to a public IP during validation and subsequently resolves to a private IP during execution, an attacker can access sensitive local services and potentially exfiltrate data. Details The vulnerability exists because the webfetch tool lacks complete DNS pinning. The application performs URL validation only once via validateParams(), but the URL is then passed unchanged to the fetchHTMLContent() function, which eventually reaches fetchWithChromedp(). The headless browser (Chromedp) resolves the hostname independently without DNS pinning, allowing a time-of-check-time-of-use (TOCTOU) attack. Validation phase (first DNS resolution): Execution phase (second DNS resolution): The original URL (not the resolved IP) is passed…

Published by the source

6 Mar 2026, 23:56 UTC

Last modified by the source

9 Mar 2026, 13:21 UTC

Source last checked

26 Oct 2026, 15:15 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-h6gw-8f77-mmmp

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# Patch Next advisory brief: CVE-2026-30858

Advisory: WeKnora has DNS Rebinding Vulnerability in web_fetch Tool that Allows SSRF to Internal Resources
IDs: CVE-2026-30858, GHSA-h6gw-8f77-mmmp
Record: https://patchnext.com/advisories/cve-2026-30858 (revision 1, source checked 26 Oct 2026, 15:15 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/Tencent/WeKnora 0.3.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/Tencent/WeKnora: affected <= 0.2.14; fixed in 0.3.0

## Suggested inspection (read-only)
- Go github.com/Tencent/WeKnora: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/Tencent/WeKnora.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-h6gw-8f77-mmmp (GitHub-reviewed advisory GHSA-h6gw-8f77-mmmp lists affected ranges: Go github.com/Tencent/WeKnora >=0 <=0.2.14)

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