Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Shlink (Packagist package shlinkio/shlink, versions up to and including 5.0.1) contains a Server-Side Request Forgery flaw in its automatic short URL title resolution feature. An attacker who can supply a crafted longUrl can cause the server to make requests to internal resources, allowing them to scan the internal network. No fixed version is listed in the source, and the source gives few further details about the required access or exact impact.
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
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 9.1 | Critical | 3.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N | GitHub Advisory Database |
- CISA KEV Not listed.
- EPSS 0.0029, the 21st percentile, on 13 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:07 UTC First seen by agentprime
- 31 Oct 2026, 14:07 UTC Confirmed by OSV