CVE-2026-55952: Erlang OTP · Improper Validation of Specified Quantity in Input
Affects Erlang OTPSource CVE Database V5
Not known to be exploited · CVSS 8.2 High : upgrade to 11.2.12.10 soon.
Data as of 14 Nov 2026, 20:58 UTC
Thin evidence
One scorer or none| CNA (EEF) | CVSS 4.0 | 8.2 |
|---|
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 46% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 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:NExploitation evidence
Disclosed: evidence found.
CVE published 2 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 14 Nov 2026.
What to do
Upgrade ssl to 11.2.12.10.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| OTPotp | Affected
| Fixed in– |
| OTPssl | Affected
| Fixed in– |
| OTPerlang/otp | Affected
| Fixed in– |
GitHubsslpkg:github/sslOther threats | Affected
| Fixed in
|
CPE configurations (1)
cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, affected Erlang/OTP installations should consider restarting the ssl application if session ticket handling is disrupted. Monitoring for unusual TLS 1.3 handshake failures may help detect exploitation attempts. Avoid relying on TLS 1.3 session tickets if possible until patched.
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.
References
- github.com/erlang/otp/security/advisories/GHSA-8c57-44c9-pc59 (opens in a new tab)
- cna.erlef.org/cves/CVE-2026-55952.html (opens in a new tab)
- osv.dev/vulnerability/EEF-CVE-2026-55952 (opens in a new tab)
- erlang.org/doc/system/versions.html (opens in a new tab)
- github.com/erlang/otp/commit/e77823e6d980b2ec0b4fe4ea3f2d098ca239e3ce (opens in a new tab)
- github.com/erlang/otp/commit/2c3e599797644310e5d4aa39c7193420e59dadff (opens in a new tab)
- github.com/erlang/otp/commit/9b5437c72fa3403a75c1aba28e5c532bc191c662 (opens in a new tab)
- github.com/erlang/otp/commit/339a279f02ce38a7b23010e56000613e19abb21f (opens in a new tab)
- github.com/erlang/otp/commit/095f744713c325acdbd18c23e397f04593c06275 (opens in a new tab)