NULL Pointer Dereference Affecting openssl-libs package, versions <1:1.1.1g-12.el8_3


high

Snyk CVSS

    Attack Complexity High
    Availability High

    Threat Intelligence

    EPSS 0.43% (75th percentile)
Expand this section
NVD
5.9 medium
Expand this section
SUSE
7.5 high
Expand this section
Red Hat
5.9 medium

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk ID SNYK-ORACLE8-OPENSSLLIBS-2573624
  • published 10 Apr 2022
  • disclosed 8 Dec 2020

How to fix?

Upgrade Oracle:8 openssl-libs to version 1:1.1.1g-12.el8_3 or higher.
This issue was patched in ELSA-2020-5476.

NVD Description

Note: Versions mentioned in the description apply only to the upstream openssl-libs package and not the openssl-libs package as distributed by Oracle. See How to fix? for Oracle:8 relevant fixed versions and status.

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).

References