CVE-2015-1793
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…
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 58.2%, higher than 99% of all known CVEs. Patch or mitigate before the next change window.
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.
- CVSS 3.0
- 6.5 MEDIUMCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
- EPSS
- 58.21% probability · 99th percentile
- Public exploits
- 1 in Exploit-DB · first 5 November 2015
- CISA KEV
- Not listed
- Weakness
- CWE-254
- Affected
- oracle/supply chain products suite · oracle/jd edwards enterpriseone tools · openssl/openssl · oracle/opus 10g ethernet switch family
- Source
- secalert@redhat.com
EPSS moved from 71.2% on 21 September 2026 to 58.2% on 4 November 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
Public exploits (1)
Entries in Exploit-DB that cite this CVE. Links go to the Exploit-DB page and to the file in the public repository; nothing is hosted here. A verified tick means the Exploit-DB team confirmed the exploit works against the stated version.
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.txtVendor Advisory
- 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.htmlPatch
- 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.htmlPatch
- http://www.oracle.com/technetwork/topics/security/cpuoct2015-2367953.htmlPatch
- 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/
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.