Severity: moderate
CVSS 4.0: 6.9 (medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U
Affected versions:
- Apache Thrift (thrift) before 0.25.0
- Apache Thrift (D language bindings) before 0.25.0
Description:
Improper Validation of Certificate with Host Mismatch in the C++ and D
libraries of Apache Thrift.
Both libraries install a default access manager for client sockets —
TSSLSocketFactory does so in C++, and the accessManager property does so in D —
which compares the peer certificate against the host
name that was connected to. That comparison walks the subjectAltName dNSName
entries first and consults the certificate Common Name afterwards. A name that
does not match yields a "skip" result rather than
a rejection, so a certificate whose subjectAltName entries are all present and
all non-matching falls through to the Common Name, which can then satisfy the
check.
RFC 6125 section 6.4.4, and RFC 9525 section 2, require that the Common Name is
not consulted when a dNSName subjectAltName is present. A certificate carrying
subjectAltName entries for one name and a
Common Name for another is therefore accepted for a connection to the second
name.
Exploitation requires an attacker positioned on the network path who holds a
certificate that chains to a certificate authority in the client's trust store
and whose Common Name matches the connected host
name. Public certificate authorities have not issued on Common Name alone for
many years, so this is principally a concern for deployments using a private or
enterprise public-key infrastructure.
This issue affects the C++ library of Apache Thrift from 0.7.0 through 0.24.0
and the D library from 0.9.0 through 0.24.0. Users should upgrade to 0.25.0.
Credit:
The ASF — found using Claude agents to study the security of open-source
projects, validated and reported by Apache Thrift. (finder)
References:
https://thrift.apache.org/
https://www.cve.org/CVERecord?id=CVE-2026-85088
