openssl-1.0.1e-58.0.1.AXS4

OpenSSL is a toolkit that implements the Secure Sockets Layer (SSL) and
Transport Layer Security (TLS) protocols, as well as a full-strength
general-purpose cryptography library.

Security Fix(es):

* openssl: EDIPARTYNAME NULL pointer de-reference (CVE-2020-1971)

For more details about the security issue(s), including the impact, a CVSS
score, acknowledgments, and other related information, refer to the CVE page(s)
listed in the References section.

CVE-2020-1971
The X.509 GeneralName type is a generic type for representing different types of
names. One of those name types is known as EDIPartyName. OpenSSL provides a
function GENERAL_NAME_cmp which compares different instances of a GENERAL_NAME
to see if they are equal or not. This function behaves incorrectly when both
GENERAL_NAMEs contain an EDIPARTYNAME. A NULL pointer dereference and a crash
may occur leading to a possible denial of service attack. OpenSSL itself uses
the GENERAL_NAME_cmp function for two purposes: 1) Comparing CRL distribution
point names between an available CRL and a CRL distribution point embedded in an
X509 certificate 2) When verifying that a timestamp response token signer
matches the timestamp authority name (exposed via the API functions
TS_RESP_verify_response and TS_RESP_verify_token) If an attacker can control
both items being compared then that attacker could trigger a crash. For example
if the attacker can trick a client or server into checking a malicious
certificate against a malicious CRL then this may occur. Note that some
applications automatically download CRLs based on a URL embedded in a
certificate. This checking happens prior to the signatures on the certificate
and CRL being verified. OpenSSL's s_server, s_client and verify tools have
support for the "-crl_download" option which implements automatic CRL
downloading and this attack has been demonstrated to work against those tools.
Note that an unrelated bug means that affected versions of OpenSSL cannot parse
or construct correct encodings of EDIPARTYNAME. However it is possible to
construct a malformed EDIPARTYNAME that OpenSSL's parser will accept and hence
trigger this attack. All OpenSSL 1.1.1 and 1.0.2 versions are affected by this
issue. Other OpenSSL releases are out of support and have not been checked.
Fixed in OpenSSL 1.1.1i (Affected 1.1.1-1.1.1h). Fixed in OpenSSL 1.0.2x
(Affected 1.0.2-1.0.2w).

Additional info:
https://access.redhat.com/errata/RHSA-2020:5566
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-1971