CVE-2015-1793
MEDIUMEPSS 99th pctlDescription
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.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Exploit Intelligence
Very high risk: more likely to be exploited than 99% of all known CVEs.
References
- http://fortiguard.com/advisory/2015-07-09-cve-2015-1793-openssl-alternative-chains-certificate-forgery
- http://ftp.netbsd.org/pub/NetBSD/security/advisories/NetBSD-SA2015-008.txt.asc
- http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10694
- http://lists.fedoraproject.org/pipermail/package-announce/2015-July/161747.html
- http://lists.fedoraproject.org/pipermail/package-announce/2015-July/161782.html
- http://marc.info/?l=bugtraq&m=143880121627664&w=2
- http://marc.info/?l=bugtraq&m=144370846326989&w=2
- http://openssl.org/news/secadv_20150709.txt
- http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20150710-openssl
- http://www.fortiguard.com/advisory/2015-07-09-cve-2015-1793-openssl-alternative-chains-certificate-forgery
- http://www.oracle.com/technetwork/security-advisory/cpuapr2016v3-2985753.html
- http://www.oracle.com/technetwork/security-advisory/cpujul2016-2881720.html
- http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html
- http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
- http://www.oracle.com/technetwork/topics/security/bulletinjul2015-2511963.html
- http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html
- http://www.oracle.com/technetwork/topics/security/cpuoct2015-2367953.html
- http://www.securityfocus.com/bid/75652
- http://www.securityfocus.com/bid/91787
- http://www.securitytracker.com/id/1032817
- http://www.slackware.com/security/viewer.php?l=slackware-security&y=2015&m=slackware-security.561427
- http://www1.huawei.com/en/security/psirt/security-bulletins/security-advisories/hw-454058.htm
- https://git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=9a0db453ba017ebcaccbee933ee6511a9ae4d1c8
- https://h20564.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c04822825
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05045763
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05184351
- https://help.ecostruxureit.com/display/public/UADCO8x/StruxureWare+Data+Center+Operation+Software+Vulnerability+Fixes
- https://kc.mcafee.com/corporate/index?page=content&id=SB10125
- https://security.gentoo.org/glsa/201507-15
- https://www.exploit-db.com/exploits/38640/
- https://www.freebsd.org/security/advisories/FreeBSD-SA-15:12.openssl.asc
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Start freeThis product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-05-06.