CVE-2026-70367 Server-side request forgery in Red Hat Enterprise Linux 10
Attackers can bypass localhost restrictions in stunnel SOCKS proxy mode using IPv4-mapped IPv6 addresses to access loopback-only services.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-70367?
CVE-2026-70367 is a medium-severity server-side request forgery vulnerability in Mobi-Com Polska Sp. z o.o. Red Hat Enterprise Linux 10, published on 4 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A Server-Side Request Forgery (SSRF) bypass vulnerability exists in “stunnel” 5.79 and lower when configured in SOCKS proxy mode. This flaw allows a client to bypass intended localhost restrictions by using IPv4-mapped IPv6 addresses (e.g., “::ffff:127.0.0.1”) or unspecified addresses ("0.0.0.0", "::"), enabling access to loopback-only services on the "stunnel" host that should not be network-reachable.
Weakness: CWE-918
Which versions are affected by CVE-2026-70367?
How do I fix CVE-2026-70367?
Upgrade to a fixed version.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-70367 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-70367 exists.
Sources
Also known as AZL-94577, DEBIAN-CVE-2026-70367, ECHO-5eef-9485-ed63, GHSA-2x69-8qrg-27gr.