Description
The Erlang/OTP ssl application does not validate that the PSK identity list and binder list carried in a TLS 1.3 ClientHello pre-shared key extension have equal length before passing them to the session ticket handler. In tls_handshake_1_3:handle_pre_shared_key/3, an OfferedPreSharedKeys record with a mismatched number of identities and binders is forwarded directly to tls_server_session_ticket:use/4, which crashes the session ticket handler process.
An unauthenticated remote attacker can send a single crafted ClientHello to a TLS 1.3 server with session tickets enabled (stateful or stateless mode) and permanently disrupt session ticket handling on that listener. New TLS 1.3 handshakes complete but subsequently crash when the server attempts to issue a session ticket, effectively making TLS 1.3 unusable on the affected listener until the ssl application is restarted. TLS 1.2 connections are not affected.
This issue affects OTP from OTP 22.2 before OTP 27.3.4.14, OTP 28.5.0.3, and OTP 29.0.3, corresponding to ssl from 9.5 before 11.2.12.10, 11.6.0.3, and 11.7.3.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Erlang | OTP | 22.2, 9.5 | — |
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 | 1:29.0.3+dfsg-1 | — |
| Debian 13 | erlang | 1:27.3.4.1+dfsg-1+deb13u3 | — |
| Debian 12 | erlang | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | erlang | 1:27.3.4.6+dfsg-1ubuntu0.2 | USN-8901-1 |
| Ubuntu 25.10 | erlang | No fix yet | — |
| Ubuntu 24.04 LTS | erlang | 1:25.3.2.8+dfsg-1ubuntu4.8 | USN-8901-1 |
| Ubuntu 22.04 LTS | erlang | 1:24.2.1+dfsg-1ubuntu0.8 | USN-8901-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | erlang | 1:22.2.7+dfsg-1ubuntu0.5+esm3 | USN-8901-1 |
| Ubuntu Pro 18.04 LTS | erlang | 1:20.2.2+dfsg-1ubuntu2+esm4 | USN-8901-1 |
| Ubuntu Pro 16.04 LTS | erlang | 1:18.3-dfsg-1ubuntu3.1+esm4 | USN-8901-1 |
| Ubuntu Pro 14.04 LTS | erlang | 1:16.b.3-dfsg-1ubuntu2.2+esm3 | USN-8901-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | erlang27 +38 | 27.3.4.17-1.hum1 | RHSA-2026:63160 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | erlang | 23.3.4.19-150300.3.39.1 | SUSE-SU-2026:3645-1 |
| SLES 15 SP7 | erlang26 | 26.2.1-150300.7.28.1 | SUSE-SU-2026:3579-1 |
| SLES 15 SP6 | erlang | 23.3.4.19-150300.3.39.1 | SUSE-SU-2026:3645-1 |
| SLES 15 SP6 | erlang26 | 26.2.1-150300.7.28.1 | SUSE-SU-2026:3579-1 |
| SLES 15 SP5 | erlang | 23.3.4.19-150300.3.39.1 | SUSE-SU-2026:3645-1 |
| SLES 15 SP4 | erlang | 23.3.4.19-150300.3.39.1 | SUSE-SU-2026:3645-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP6 | erlang | 23.3.4.19-150300.3.39.1 | SUSE-SU-2026:3645-1 |
| SLES for SAP 15 SP6 | erlang26 | 26.2.1-150300.7.28.1 | SUSE-SU-2026:3579-1 |
| SLES for SAP 15 SP5 | erlang | 23.3.4.19-150300.3.39.1 | SUSE-SU-2026:3645-1 |
| SLES for SAP 15 SP4 | erlang | 23.3.4.19-150300.3.39.1 | SUSE-SU-2026:3645-1 |
| SLE HPC 15 SP5 | erlang | 23.3.4.19-150300.3.39.1 | SUSE-SU-2026:3645-1 |
| SLE HPC 15 SP4 | erlang | 23.3.4.19-150300.3.39.1 | SUSE-SU-2026:3645-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | erlang | 28.5.0.4-1.1 | openSUSE-SU-2026:11559-1 |
| openSUSE Tumbleweed | erlang27 | 27.1.3-3.1 | openSUSE-SU-2026:11560-1 |
Advisories 9
- RHSA-2026:63160 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Oct 20, 2026
- USN-8901-1 erlang vulnerabilities Ubuntu Security Notices (USN) · Oct 8, 2026
- WID-SEC-2026-2194 Erlang/OTP: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 28, 2026
- WID-SEC-2026-3403 Oracle Communications: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 24, 2026
- NCSC-2026-0375 Kwetsbaarheden verholpen in Oracle Communications NCSC-NL (Netherlands) · Sep 16, 2026
- openSUSE-SU-2026:11560-1 erlang27-27.1.3-3.1 on GA media SUSE / openSUSE Security Updates · Aug 21, 2026
- openSUSE-SU-2026:11559-1 erlang-28.5.0.4-1.1 on GA media SUSE / openSUSE Security Updates · Aug 21, 2026
- SUSE-SU-2026:3645-1 Security update for erlang SUSE / openSUSE Security Updates · Aug 21, 2026
- SUSE-SU-2026:3579-1 Security update for erlang26 SUSE / openSUSE Security Updates · Aug 12, 2026
References
- Denial-of-Service for TLS-1.3 server Using Session Tickets vendor-advisory related
- EEF CNA record for CVE-2026-55952 related
- OSV record EEF-CVE-2026-55952 related
- Erlang/OTP version ordering
- Introducing commit 339a279 in erlang/otp related
- Fix commit 095f744 in erlang/otp patch
- Fix commit e77823e in erlang/otp patch
- Fix commit 2c3e599 in erlang/otp patch
- Fix commit 9b5437c in erlang/otp patch