CVE-2026-117666

LOWCVSS 9.1 · CRITICAL

Signal is active with 1 mentions in latest observed window

Immediate actions

  • Track advisory updates for patch or workaround availability

Recommended action window: Monitor and triage in normal cycle

NVD description

Improper Validation of Certificate with Host Mismatch vulnerability in deadtrickster ssl_verify_fun allows an adversary in the middle to impersonate a TLS peer via a certificate that carries a partial-label wildcard. try_match_wildcard/4 in src/ssl_verify_hostname.erl anchors only the text before and after the * of an identifier such as f*.example.net, so the wildcard also consumes dots and the certificate is accepted for f.evil.example.net. RFC 6125 confines a wildcard to the left-most label. The same matcher lets *.168.1.1 match the IP literal 192.168.1.1. Whole-label wildcards are matched correctly. Erlang/OTP 20.0 and later check the hostname in ssl before a user verify_fun sees valid_peer, so a client that keeps server_name_indication set rejects the mismatch regardless. Exposed are clients that disable SNI, servers that verify client certificate hostnames with this library, and direct callers of verify_cert_hostname/2. This issue affects ssl_verify_fun: from 1.0.1 before 1.1.8.

0.0/ 10 priority

Sources & remediation

Weakness type (CWE)
CWE-297

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

NONE

Momentum

NONE

Threat summary

  • 1 mentions across 1 observed day

What's happening

  • 1 total mentions across 1 day

Deep dive

Activity timeline1 mentions / 1d
00111Mentions · 2026-10-30: 110-30
Referenced assets1 URL
Full discourse1 post
  • cve.now@cvedotnow

    🔴 deadtrickster ssl_verify_fun: wildcard certificate spoofing in hostname matching (CVE-2026-117666) An attacker between a client and server can present a crafted certificate to impersonate the TLS peer. Patch → 1.1.8 https://cve.now/CVE-2026-117666?utm_source=x&utm_medium=social&utm_campaign=cvedotnow&utm_content=critical

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