Description
There is a type confusion vulnerability relating to X.400 address processing inside an X.509 GeneralName. X.400 addresses were parsed as an ASN1_STRING but the public structure definition for GENERAL_NAME incorrectly specified the type of the x400Address field as ASN1_TYPE. This field is subsequently interpreted by the OpenSSL function GENERAL_NAME_cmp as an ASN1_TYPE rather than an ASN1_STRING. When CRL checking is enabled (i.e. the application sets the X509_V_FLAG_CRL_CHECK flag), this vulnerability may allow an attacker to pass arbitrary pointers to a memcmp call, enabling them to read memory contents or enact a denial of service. In most cases, the attack requires the attacker to provide both the certificate chain and CRL, neither of which need to have a valid signature. If the attacker only controls one of these inputs, the other input must already contain an X.400 address as a CRL distribution point, which is uncommon. As such, this vulnerability is most likely to only affect applications which have implemented their own functionality for retrieving CRLs over a network.
Affected products
openssl: openssl; stormshield: stormshield management center; stormshield: stormshield network security
References10
- git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=2c6c9d439b… PatchVendor Advisory
- git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=2f7530077e… PatchVendor Advisory
- git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=fd2af07dc0… PatchVendor Advisory
- www.openssl.org/news/secadv/20230207.txt Vendor Advisory
- git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=2c6c9d439b… PatchVendor Advisory
- git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=2f7530077e… PatchVendor Advisory
- git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=fd2af07dc0… PatchVendor Advisory
- www.openssl.org/news/secadv/20230207.txt Vendor Advisory
- ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-3.6.2-relnotes.txt Third Party Advisory
- ftp.openbsd.org/pub/OpenBSD/patches/7.2/common/018_x509.patch.s… Third Party Advisory
Metrics
- CVSS 3.1
-
7.4
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 69% percentile: 99 · as of 6 November 2026
- CWE
- CWE-843
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