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Advisory record · GHSA-pph6-vfjv-vpjw

ToolHive: SSRF guard misses IPv6 NAT64 ranges (64:ff9b::/96, 64:ff9b:1::/48), allowing metadata/internal access behind a NAT64 gateway

CVSS 2.9 LowEPSS 0.0033 · 26th percentile

Published by the GitHub Advisory Database at 15 Jul 2026, 21:51 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

PackageEcosystemAffectedFixed in
github.com/stacklok/toolhiveGo<0.29.10.29.1
Identifiers
GHSA-pph6-vfjv-vpjw · CVE-2026-54450 · GO-2026-5996
Weakness (CWE)
CWE-918
Tags
Published
15 Jul 2026
Updated
21 Jul 2026

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

The ToolHive package github.com/stacklok/toolhive, versions before 0.29.1, has an SSRF guard (IsPrivateIP) that does not recognize the IPv6 NAT64 ranges 64:ff9b::/96 and 64:ff9b:1::/48, so NAT64-encoded internal addresses such as those for the cloud metadata address are treated as public. An attacker who can supply a URL reaching this guard, such as an OAuth client ID metadata URL, can make ToolHive probe internal addresses when deployed behind a NAT64 gateway, though the source describes this as a blind reachability probe rather than credential theft. Upgrade to version 0.29.1.

Written 6 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

ScoreRatingCVSSVectorSource
2.9 Low 4.0 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P CNA (GitHub_M)
  • CISA KEV Not listed.
  • EPSS 0.0033, the 26th percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

  1. 31 Oct 2026, 14:59 UTC First seen by agentprime
  2. 31 Oct 2026, 14:59 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.