GHSA-vp96-hxj8-p424

    Dashboard / Vulnerabilities / GHSA-vp96-hxj8-p424

    GHSA-vp96-hxj8-p424

    Published: 16 Mar 2026Last Modified: 10 Sept 2026

    Summary: pyOpenSSL allows TLS connection bypass via unhandled callback exception in set_tlsext_servername_callback

    Details: If a user provided callback to `set_tlsext_servername_callback` raised an unhandled exception, this would result in a connection being accepted. If a user was relying on this callback for any security-sensitive behavior, this could allow bypassing it. Unhandled exceptions now result in rejecting the connection. Credit to **Leury Castillo** for reporting this issue.

    References: https://github.com/pyca/pyopenssl/security/advisories/GHSA-vp96-hxj8-p424, https://nvd.nist.gov/vuln/detail/CVE-2026-27448, https://github.com/pyca/pyopenssl/commit/d41a814759a9fb49584ca8ab3f7295de49a85aa0, https://github.com/pyca/pyopenssl, https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rst#L27

    Affected packages

    Package

    Name: pyopenssl

    Purl: pkg:pypi/pyopenssl

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0.14.0
    Fixed -26.0.0

    Affected versions

    0.14

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High