CVE-2026-48860 Distribution-over-TLS LAN allowlist silently bypassed due to sockname/peername confusion in inet_tls_dist
Attackers with valid TLS certificates can bypass LAN allowlists in Erlang distribution to execute arbitrary code and escalate privileges.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-48860?
CVE-2026-48860 is a high-severity authentication bypass vulnerability in Erlang OTP, published on 10 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Reliance on IP Address for Authentication vulnerability in Erlang/OTP ssl (inet_tls_dist module) allows unauthenticated bypass of the distribution-over-TLS LAN allowlist.
The inet_tls_dist:check_ip/1 function, which enforces a LAN allowlist for Erlang distribution over TLS, calls inet:sockname/1 instead of inet:peername/1 to obtain the peer's IP address. Because inet:sockname/1 returns the local socket address, both the local IP and the supposed peer IP resolve to the same value, causing the subnet mask comparison to always succeed regardless of the actual remote address. Any holder of a CA-signed TLS certificate can therefore bypass the LAN restriction and gain full Erlang distribution access to the node, including rpc:call/4 and code:load_binary/3.
This vulnerability is associated with program file lib/ssl/src/inet_tls_dist.erl.
This issue affects OTP from OTP 26.0 before OTP 27.3.4.13, OTP 28.5.0.2, and OTP 29.0.2, corresponding to ssl from 11.0 before 11.2.12.9, 11.6.0.2, and 11.7.2.
Which versions are affected by CVE-2026-48860?
It affects 2 products.
Products include Erlang Erlang\/Otp, Erlang Erlang\/Ssl.
How do I fix CVE-2026-48860?
Upgrade to a fixed version.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-48860 being exploited?
There is no known exploitation of CVE-2026-48860 in the wild and no public exploit code.
Other vulnerabilities in Erlang OTP
- CVE-2022-37026 Auth bypass in n/a
- CVE-2016-10253 Memory corruption in n/a
- CVE-2026-55953 TLS 1.2 and DTLS client accepts unoffered anonymous cipher suite, bypassing server authentication
- CVE-2026-49759 Stack buffer overflow in SCTP error cause parsing in inet_drv allows remote VM crash
- CVE-2026-58227 TLS/DTLS denial of service via unbounded recursion on cross-signed peer certificate chain
Sources
Also known as AZL-90123, DEBIAN-CVE-2026-48860, EEF-CVE-2026-48860, GHSA-gp7x-mfv6-52cv, UBUNTU-CVE-2026-48860.