CVE-2026-110240 Lancet through 2.3.9 SSRF Protection Bypass via netutil.IsInternalIP
Attackers can bypass SSRF protections in the Lancet library to access internal services or cloud metadata via misclassified IPv6 addresses.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-110240?
CVE-2026-110240 is a medium-severity server-side request forgery vulnerability in duke-git lancet, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Lancet through 2.3.9 contains an SSRF protection bypass vulnerability in netutil.IsInternalIP that misclassifies IPv6 private, link-local, CGNAT and transition addresses as external. Attackers can supply hostnames resolving to these address forms, including NAT64, 6to4 or Teredo embedding internal IPv4, to reach internal services or cloud metadata endpoints.
Weakness: CWE-918
Which versions are affected by CVE-2026-110240?
How do I fix CVE-2026-110240?
No fix has been published for CVE-2026-110240 yet. Limit exposure of the affected software until one is available.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-110240 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-110240 exists.
Sources
Also known as GHSA-q6h5-5jp8-6c7q.