Vulnerability record · CVE-2026-55952 · published 2 July 2026
CVE-2026-55952: Erlang\/otp vulnerability
Erlang · Erlang\/Otp
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 29.0.3, OTP 28.5.0.3 and OTP 27.3.4.14, corresponding to ssl from 9.5 before 11.7.3, 11.6.0.3 and 11.2.12.10.
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 29.0.3, OTP 28.5.0.3 and OTP 27.3.4.14, corresponding to ssl from 9.5 before 11.7.3, 11.6.0.3 and 11.2.12.10.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:
Affected products
2 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://cna.erlef.org/cves/CVE-2026-55952.html | MitigationVendor Advisory |
| https://github.com/erlang/otp/commit/2c3e599797644310e5d4aa39c7193420e59dadff | Patch |
| https://github.com/erlang/otp/commit/9b5437c72fa3403a75c1aba28e5c532bc191c662 | Patch |
| https://github.com/erlang/otp/commit/e77823e6d980b2ec0b4fe4ea3f2d098ca239e3ce | Patch |
| https://github.com/erlang/otp/security/advisories/GHSA-8c57-44c9-pc59 | Vendor Advisory |
| https://osv.dev/vulnerability/EEF-CVE-2026-55952 | MitigationThird Party Advisory |
| https://www.erlang.org/doc/system/versions.html#order-of-versions | Release Notes |
Track CVE-2026-55952 inside VULONE
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-55952), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.
