All vulnerabilities
CVE-2026-85738GHSA-9hpq-mrpx-mcxg

TREK: SSRF Guard Bypass via IPv6 Transition Addresses (NAT64/6to4)

liketrek TREK
Open in ThreatlineRecord JSON
CVSS
6.3Medium
ExploitationPublic exploit codeCISA's assessment says proof of concept code is public, assessed 28 Sep 2026. Not in the KEV catalogCISA via CVE List
Exploit odds (EPSS)0.30%Chance of exploitation activity in the next 30 days, higher than 21% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed inNone listedNo source names a fixed version. Check the vendor advisory below
Published24 Sep 2026Updated 28 Sep 2026CVE List

What fixes it

No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.

Description

TREK is a collaborative travel planner. Prior to 3.4.0, the checkSsrf logic in server/src/utils/ssrfGuard.ts does not recognize NAT64, 6to4, or Teredo IPv6 transition addresses that encode an IPv4 destination. An authenticated user who controls a DNS record can supply a URL whose AAAA result is a transition address embedding a private, loopback, or link-local IPv4 target, and isAlwaysBlocked and isPrivateNetwork classify the address as allowed. In a deployment that routes the applicable transition format, user-facing imports, webhooks, integrations, or plugin egress can reach internal services or cloud metadata and expose returned information. This issue is fixed in version 3.4.0.

Text from CVE List

Affected versions 1

  • TREKaffected: < 3.4.0CVE List

References 4