--- title: "CVE-2015-1793: The X509_verify_cert function… | CubePath" description: "The X509_verify_cert function in crypto/x509/x509_vfy.c in OpenSSL 1.0.1n, 1.0.1o, 1.0.2b, and 1.0.2c does not properly process X.509 Basic Constraints…" language: en source: https://cubepath.com/security/cve/CVE-2015-1793 --- # CVE-2015-1793: The X509_verify_cert function… | CubePath ## Description The X509\_verify\_cert function in crypto/x509/x509\_vfy.c in OpenSSL 1.0.1n, 1.0.1o, 1.0.2b, and 1.0.2c does not properly process X.509 Basic Constraints cA values during identification of alternative certificate chains, which allows remote attackers to spoof a Certification Authority role and trigger unintended certificate verifications via a valid leaf certificate. Official description from the CVE record, published by redhat. Copyright © 1999-2026 The MITRE Corporation. See [/security/cve/legal](https://cubepath.com/security/cve/legal) for the CVE license. [View the record on cve.org](https://www.cve.org/CVERecord?id=CVE-2015-1793) ## Key data ### EPSS Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days. Score 0.58213 (58.2% probability) Percentile 99.1% Scores of Nov 10, 2026 Model v2026.06.15 ## References Links listed in the CVE record. They lead to other sites, which CubePath does not control. - [SSRT102180](http://marc.info/?l=bugtraq&m=143880121627664&w=2) (marc.info) vendor-advisory - [h20564.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?d…](https://h20564.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr%5Fna-c04822825) - [1032817](http://www.securitytracker.com/id/1032817) (securitytracker.com) vdb-entry - [oracle.com/technetwork/security-advisory/cpujul2016-2881720…](http://www.oracle.com/technetwork/security-advisory/cpujul2016-2881720.html) - [GLSA-201507-15](https://security.gentoo.org/glsa/201507-15) (security.gentoo.org) vendor-advisory - [www1.huawei.com/en/security/psirt/security-bulletins/securi…](http://www1.huawei.com/en/security/psirt/security-bulletins/security-advisories/hw-454058.htm) - [oracle.com/technetwork/topics/security/cpuoct2015-2367953.h…](http://www.oracle.com/technetwork/topics/security/cpuoct2015-2367953.html) - [oracle.com/technetwork/topics/security/cpujan2016-2367955.h…](http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html) - [20150710 OpenSSL Alternative Chains Certificate Forgery Vulnerability (July 2015) Affecting Cisco Products](http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20150710-openssl) (tools.cisco.com) vendor-advisory - [git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=9a0db453ba017…](https://git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=9a0db453ba017ebcaccbee933ee6511a9ae4d1c8) - [FreeBSD-SA-15:12](https://www.freebsd.org/security/advisories/FreeBSD-SA-15:12.openssl.asc) (freebsd.org) vendor-advisory - [h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?d…](https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr%5Fna-c05184351) - [FEDORA-2015-11414](http://lists.fedoraproject.org/pipermail/package-announce/2015-July/161747.html) (lists.fedoraproject.org) vendor-advisory - [oracle.com/technetwork/topics/security/bulletinjul2015-2511…](http://www.oracle.com/technetwork/topics/security/bulletinjul2015-2511963.html) - [oracle.com/technetwork/security-advisory/cpuoct2016-2881722…](http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html) - [openssl.org/news/secadv\_20150709.txt](http://openssl.org/news/secadv%5F20150709.txt) - [oracle.com/technetwork/security-advisory/cpuoct2017-3236626…](http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html) - [help.ecostruxureit.com/display/public/UADCO8x/StruxureWare+…](https://help.ecostruxureit.com/display/public/UADCO8x/StruxureWare+Data+Center+Operation+Software+Vulnerability+Fixes) - [HPSBGN03424](http://marc.info/?l=bugtraq&m=144370846326989&w=2) (marc.info) vendor-advisory - [FEDORA-2015-11475](http://lists.fedoraproject.org/pipermail/package-announce/2015-July/161782.html) (lists.fedoraproject.org) vendor-advisory - [fortiguard.com/advisory/2015-07-09-cve-2015-1793-openssl-al…](http://fortiguard.com/advisory/2015-07-09-cve-2015-1793-openssl-alternative-chains-certificate-forgery) - [kc.mcafee.com/corporate/index?page=content&id=SB10125](https://kc.mcafee.com/corporate/index?page=content&id=SB10125) - [fortiguard.com/advisory/2015-07-09-cve-2015-1793-openssl-al…](http://www.fortiguard.com/advisory/2015-07-09-cve-2015-1793-openssl-alternative-chains-certificate-forgery) - [oracle.com/technetwork/security-advisory/cpuapr2016v3-29857…](http://www.oracle.com/technetwork/security-advisory/cpuapr2016v3-2985753.html) - [91787](http://www.securityfocus.com/bid/91787) (securityfocus.com) vdb-entry - [h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?d…](https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr%5Fna-c05045763) - [75652](http://www.securityfocus.com/bid/75652) (securityfocus.com) vdb-entry - [kb.juniper.net/InfoCenter/index?page=content&id=JSA10694](http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10694) - [38640](https://www.exploit-db.com/exploits/38640/) (exploit-db.com) exploit - [SSA:2015-190-01](http://www.slackware.com/security/viewer.php?l=slackware-security&y=2015&m=slackware-security.561427) (slackware.com) vendor-advisory - [NetBSD-SA2015-008](http://ftp.netbsd.org/pub/NetBSD/security/advisories/NetBSD-SA2015-008.txt.asc) (ftp.netbsd.org) vendor-advisory ## Timeline 1. ID reserved Feb 17, 2015 2. Record published Jul 9, 2015 3. Record last updated Aug 6, 2024 ## Look up another CVE ## About CubePath CubePath is a cloud provider with data centers in Europe and the United States. It offers VPS, bare metal servers and DDoS protection. [Cloud VPS](https://cubepath.com/vps) [DDoS protection](https://cubepath.com/ddos-protection) Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 20:00 UTC. [Sources and licenses](https://cubepath.com/security/cve/legal)