CVE-2026-89422: Erlang/OTP ssl · Key Exchange Without Entity Authentication Vulnerability
Affects erlangSource GCVE Database
Not known to be exploited · CVSS 9.3 Critical · fixed in 1:22.2.7+dfsg-1ubuntu0.5+esm3 : patch erlang as a priority.
Data as of 8 Nov 2026, 23:24 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 40% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1:22.2.7+dfsg-1ubuntu0.5+esm3, 1:24.2.1+dfsg-1ubuntu0.8, 1:25.3.2.8+dfsg-1ubuntu4.8 +1
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 22 Sep 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 8 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10erlangpkg:deb/ubuntu/erlang?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSerlangpkg:deb/ubuntu/erlang?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSerlangpkg:deb/ubuntu/erlang?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 22.04 LTSerlangpkg:deb/ubuntu/erlang?arch=source&distro=jammyOther threats | Affected
| Fixed in
|
Ubuntu Pro 20.04 LTSerlangpkg:deb/ubuntu/erlang?arch=source&distro=esm-infra/focalOther threats | Affected
| Fixed in
|
Ubuntu Pro 18.04 LTSerlangpkg:deb/ubuntu/erlang?arch=source&distro=esm-infra/bionicOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available to address this vulnerability. Users should update Erlang/OTP to versions 27.3.4.18 or later, 28.5.0.7 or later, or 29.1.1 or later as applicable. Applying the official fix will prevent the improper handling of the pre_shared_key extension and restore proper certificate validation during TLS 1.3 handshakes.
Description
A vulnerability in Erlang/OTP ssl allows a peer responding to a TLS 1.3 client connection to impersonate the intended server by bypassing certificate validation. This occurs due to improper handling of a pre_shared_key extension in the ServerHello message, which the client never offered, causing the client to skip certificate verification steps. The issue affects default client configurations using TLS 1.3 and impacts OTP versions from 22.2 up to but not including 27.3.4.18, 28.5.0.7, and 29.1.1. A patch is available to address this issue.
References
- ubuntu.com/security/CVE-2026-89422 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89422 (opens in a new tab)
- cna.erlef.org/cves/CVE-2026-89422.html (opens in a new tab)
- github.com/erlang/otp/commit/21b8a1b0ad0adf200682b3854bc50114ab2b8c62 (opens in a new tab)
- github.com/erlang/otp/commit/98c66c858113949c4262d26cd7d426c4b09d2b35 (opens in a new tab)
- github.com/erlang/otp/commit/afec5156361bb50d3607c7c1a453c19b9149b324 (opens in a new tab)
- github.com/erlang/otp/commit/fd1d9d07fc92ec0d59f96dfb66182195882bb7dd (opens in a new tab)
- github.com/erlang/otp/security/advisories/GHSA-rgxr-4g4w-j875 (opens in a new tab)
- osv.dev/vulnerability/EEF-CVE-2026-89422 (opens in a new tab)
- erlang.org/doc/system/versions.html (opens in a new tab)
- ubuntu.com/security/notices/USN-8901-1 (opens in a new tab)
- msrc.microsoft.com/csaf/vex/2026/msrc_cve-2026-89422.json (opens in a new tab)
- support.microsoft.com/lifecycle (opens in a new tab)
- first.org/cvss (opens in a new tab)