CVE-2026-19553

A flaw was found in Python. When establishing secure connections using the SSLContext.wrapbio function with hostname checking enabled, the module fails to validate that a target server hostname is supplied. Because of this missing check, certificate hostname verification is silently skipped rathe...

CVE-2026-19553 SSLContext.wrap_bio() missing validation of server_hostname parameter

ssl.SSLContext.wrapbio didn't require the serverhostname argument to not be None if ssl.SSLContext.checkhostname was set. Due to a missing parameter check in SSLObject, if the serverhostname argument isn't supplied then hostname verification would be silently skipped. This defect could lead to...

CVE-2026-19553

The Python ssl.SSLContext.wrap_bio() method fails to require a non-None server_hostname argument even when ssl.SSLContext.check_hostname is enabled. Due to a missing parameter check in SSLObject , omitting the server_hostname argument causes certificate hostname verification to be silently skippe...

EUVD-2026-90078

ssl.SSLContext.wrapbio didn't require the serverhostname argument to not be None if ssl.SSLContext.checkhostname was set. Due to a missing parameter check in SSLObject, if the serverhostname argument isn't supplied then hostname verification would be silently skipped. This defect could lead to...

CVE-2026-19553

ssl.SSLContext.wrapbio didn't require the serverhostname argument to not be None if ssl.SSLContext.checkhostname was set. Due to a missing parameter check in SSLObject, if the serverhostname argument isn't supplied then hostname verification would be silently skipped. This defect could lead to...