Is CVE-2026-55952 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-55952 being exploited in the wild.

How severe is CVE-2026-55952?

Informational severity, with a CVSS score of 8.2, published 2 July 2026.

Which products and versions are affected?

Erlang OTP 22.2 before 29.0.3, 28.5.0.3, and 27.3.4.14; Erlang Ssl 9.5 before 11.7.3, 11.6.0.3, and 11.2.12.10.

Is there a fix for CVE-2026-55952?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-55952 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-55952?

Check whether you run Erlang OTP or Erlang Ssl at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-55952: Erlang OTP denial of service in SSL TLS 1.3 session ticket handling

CVE-2026-55952 · Severity: info · CVSS 8.2 · Published 2026-07-02

A vulnerability in the Erlang/OTP SSL library can allow a remote attacker to crash the component responsible for handling secure session tickets. By sending a specially crafted connection request, an attacker can permanently disrupt the server's ability to process new TLS 1.3 connections that use session tickets. This results in a denial-of-service condition for secure web traffic until the affected application is manually restarted.

Technologies: Erlang OTP, Erlang Ssl. Vendors: Erlang.

Quick answers

Is CVE-2026-55952 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-55952 being exploited in the wild.
How severe is CVE-2026-55952?: Informational severity, with a CVSS score of 8.2, published 2 July 2026.
Which products and versions are affected?: Erlang OTP 22.2 before 29.0.3, 28.5.0.3, and 27.3.4.14; Erlang Ssl 9.5 before 11.7.3, 11.6.0.3, and 11.2.12.10.
Is there a fix for CVE-2026-55952?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-55952 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-55952?: Check whether you run Erlang OTP or Erlang Ssl at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A denial-of-service vulnerability exists in the Erlang/OTP ssl application due to improper validation of the Pre-Shared Key (PSK) extension in TLS 1.3. Specifically, the function 'tls_handshake_1_3:handle_pre_shared_key/3' does not verify that the PSK identity list and binder list have equal lengths. An unauthenticated remote attacker can exploit this by sending a crafted ClientHello with mismatched list lengths, causing the 'tls_server_session_ticket' process to crash. This permanently disrupts session ticket handling on the affected listener until a restart. The issue is fixed in OTP versions 29.0.3, 28.5.0.3, and 27.3.4.14.

Affected products

Erlang OTP 22.2 before 29.0.3, 28.5.0.3, and 27.3.4.14
Erlang ssl 9.5 before 11.7.3, 11.6.0.3, and 11.2.12.10

Timeline

2026-07-02: advisory
2026-07-02: disclosed

References

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