Description
OTP is a set of Erlang libraries, which consists of the Erlang runtime system, a number of ready-to-use components mainly written in Erlang, and a set of design principles for Erlang programs. A regression was introduced into the ssl application of OTP starting at OTP-25.3.2.8, OTP-26.2, and OTP-27.0, resulting in a server or client verifying the peer when incorrect extended key usage is presented (i.e., a server will verify a client if they have server auth ext key usage and vice versa).
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| erlang | otp | >= 25.3.2.8, <= 25.3.2.16, >= 26.2, <= 26.2.5.6, >= 27.0, <= 27.1.3 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | erlang | 1:27.2+dfsg-1 | — |
| Debian 13 | erlang | 1:27.2+dfsg-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | erlang | 1:25.3.2.8+dfsg-1ubuntu4.6 | USN-7961-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | erlang | 26.2.5.6-1 | — |
Advisories 1
- USN-7961-1 erlang vulnerability Ubuntu Security Notices (USN) · Apr 22, 2026