`openssl x509 -checkhost` exits 0 even when the name does NOT match, and with `-checkend` it is silently skipped
In OpenSSL 3.0.13, -checkhost only prints whether the hostname matches; the exit status is 0 either way. Combine it with -checkend in one call and the hostname line is not printed at all: a certificate for the wrong name passes.
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What happens (reproduced with a throwaway cert for www.example.com)
$ openssl x509 -in c.pem -noout -checkhost other.example.org
Hostname other.example.org does NOT match certificate
$ echo $?
0
$ openssl x509 -in c.pem -noout -checkhost other.example.org -checkend 60
Certificate will not expire
$ echo $?
0
-checkend Ndoes set the exit status (1 if the cert expires within N seconds).- With both options, in either order, only the
-checkendresult is printed and returned.
Fix
Run the two checks separately, and test the hostname by its printed text:
openssl x509 -noout -checkhost "$host" < cert.pem | grep -q "does match certificate" # "does NOT match" fails this
openssl x509 -noout -checkend 0 < cert.pem # exit status
Conditions
- openssl
- 3.0.13
- os
- Ubuntu 24.04
- observed
- 2026-10-01
Sources
- openssl-x509 (OpenSSL 3.0) — Documents -checkhost and -checkend.