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TI-2026-74334 Aliases CVE-2026-94200

Erlang OTP ssl client crash from malicious NewSessionTicket early_data

Priority LOW 36CWE-1288Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 1 fixed, 3 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat.

Summary

Erlang OTP ssl from OTP 23.3 before OTP 27.3.4.19, OTP 28.5.0.8, and OTP 29.1.2 is affected. The TLS 1.3 client decodes NewSessionTicket extensions as if they came from EncryptedExtensions, so it accepts a zero length early_data extension (CWE-1288). A malicious TLS 1.3 server can crash the client's node wide ticket store on the next automatic resumption, and repeated crashes can take down ssl for all connections on that node.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

Description from the CNA

Improper Validation of Consistency within Input vulnerability in Erlang OTP ssl (tls_handshake_1_3, ssl_handshake and tls_client_ticket_store modules) allows a malicious TLS 1.3 server to cause a denial of service of the ssl application on the client node. The TLS 1.3 client decodes the extensions of a NewSessionTicket message as if they came from EncryptedExtensions. It therefore accepts a 0-length early_data extension, a form that is only valid in ClientHello and EncryptedExtensions. With {session_tickets, auto}, the client stores the ticket in the node-global tls_client_ticket_store. On the next automatic resumption, tls_handshake_1_3:get_max_early_data/1 crashes the store with a case_clause. Repeated crashes can exceed the restart intensity of the ssl supervisors, which use the rest_for_one strategy, and take down ssl for all connections on the node. This issue affects OTP from OTP 23.3 before OTP 27.3.4.19, OTP 28.5.0.8, and OTP 29.1.2, corresponding to ssl from 10.3 before 11.2.12.14, 11.6.0.7, and 11.7.8.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00461 40th percentileScored 2026-11-07
Fix Partial Red Hat: 1 advisoryRed Hat: 1 fixed, 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ErlangOTP23.3 and later—No fix listedCNA
ErlangOTP10.3 and later—No fix listedCNA
  • OTP VendorErlang Affected 23.3 and later Fixed in — No fix listed CNA
  • OTP VendorErlang Affected 10.3 and later Fixed in — No fix listed CNA

CPE names CNA · 1

CPEVersionsRoleVendor
cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*——Erlang
  • cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:* Versions — — ·Erlang

Remediation

Upgrade Erlang OTP to 27.3.4.19, 28.5.0.8, or 29.1.2, which contain ssl 11.2.12.14, 11.6.0.7, and 11.7.8 respectively. Red Hat fixes Red Hat Hardened Images in RHSA-2026:83217. Red Hat lists Red Hat OpenStack Platform 16.2, 17.1, and 18.0 as affected with no fix available.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

Red Hat 1 advisory

  • RHSA-2026:83217 Released 2026-10-14 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images erlang27-27.3.4.19-0.1.hum1@aarch64, erlang27-27.3.4.19-0.1.hum1@s390x, erlang27-27.3.4.19-0.1.hum1@src +47

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat OpenStack Platform 16.2AffectedNo fix yet
Red Hat OpenStack Platform 17.1AffectedNo fix yet
Red Hat OpenStack Platform 18.0AffectedNo fix yet
Red Hat Hardened ImagesFixed RHSA-2026:83217
Not affected: 1 product
  • Red Hat OpenStack Platform 13 (Queens)

Timeline

  1. 2026-10-15 Threatist record created from CVE-2026-94200
  2. 2026-10-16 Priority changed: MEDIUM → LOW
  3. 2026-10-18 CISA SSVC decision points changed
  4. 2026-10-20 Fix available: RHSA-2026:83217 · Red Hat
  5. 2026-10-20 Fix available: Red Hat Hardened Images · Red Hat
  6. 2026-10-20 CVSS score added · Red Hat
  7. 2026-10-30 Affected versions changed · Red Hat

References

Patch 3

Advisory 1

Other 4

  • TI-2025-23504 Erlang/OTP SSH Vulnerable to Pre-Authentication RCE KEVCVSS 3.1CRITICAL 10.0
  • TI-2026-48954 httpd parks a request worker indefinitely on a malformed chunk size sent after the headers CVSS 4.0HIGH 8.7
  • TI-2023-26623 The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6… CVSS 3.1MEDIUM 5.9
  • TI-2026-71037 Path traversal in rebar3 via unvalidated dependency app names CVSS 4.0HIGH 7.5
  • TI-2024-36042 ssl fails to validate incorrect extened key usage CVSS 3.1MEDIUM 5.5
  • TI-2020-10791 Rebar3 versions 3.0.0-beta.3 to 3.13.2 are vulnerable to OS command injection via URL… CVSS 3.1CRITICAL 9.8
See all 80 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences