OkHttp through 5.5.1 contains an improper certificate validation vulnerability in CertificatePinner that skips pin
Source GCVE Database
Not known to be exploited · CVSS 6.3 Medium.
Data as of 15 Nov 2026, 16:39 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 6.3 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 4.8 |
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 15 Nov 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
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| SquareOkHttp | Affected
| Fixed in– |
MavenOkHttppkg:maven/OkHttpOther 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
Until a fix is available, avoid using trailing-dot hostnames with CertificatePinner or implement additional hostname normalization as a temporary mitigation.
Description
OkHttp versions through 5.5.1 have a vulnerability in the CertificatePinner component where pin checks are skipped for hostnames with trailing dots due to improper normalization. This allows network attackers with a CA-trusted certificate that does not match the configured pins to intercept or modify TLS traffic when applications request the trailing-dot form of pinned hosts.
References
- nvd.nist.gov/vuln/detail/CVE-2026-129482 (opens in a new tab)
- github.com/lysine-dev/okhttp/issues/9724 (opens in a new tab)
- github.com/lysine-dev/okhttp/pull/9734 (opens in a new tab)
- github.com/lysine-dev/okhttp/commit/30aa589761a9b4f5fe84c00e21e5ab44b22bd7c1 (opens in a new tab)
- github.com/lysine-dev/okhttp/blob/parent-5.5.1/okhttp/src/commonJvmAndroid/kotlin/okhttp3/CertificatePinner.kt (opens in a new tab)
- vulncheck.com/advisories/okhttp-through-5.5.1-certificate-pinning-bypass-via-trailing-dot-hostname (opens in a new tab)