openssl: alternative chains certificate forgery
Published Jul 9, 2015
6.5
MEDIUMCVSS 3.0
EPSS 62.39%
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.
Affected products
No data.
Configuration 1
- 6.1.2.2
- 6.1.3.0
- 6.2.0
Configuration 2
- 9.1
- 9.2
Configuration 3
Configuration 4
- ≤ 2.0.0.6
No data.
Red Hat Enterprise Linux 4
openssl
Not affected
Red Hat Enterprise Linux 5
openssl
Not affected
Red Hat Enterprise Linux 5
openssl097a
Not affected
Red Hat Enterprise Linux 6
openssl
Not affected
Red Hat Enterprise Linux 6
openssl098e
Not affected
Red Hat Enterprise Linux 7
openssl
Not affected
Red Hat Enterprise Linux 7
openssl098e
Not affected
Red Hat JBoss Enterprise Application Platform 6
openssl
Not affected
Red Hat JBoss Enterprise Web Server 1
openssl
Not affected
Red Hat JBoss Enterprise Web Server 2
openssl
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 4 | openssl | Not affected | n/a |
| Red Hat Enterprise Linux 5 | openssl | Not affected | n/a |
| Red Hat Enterprise Linux 5 | openssl097a | Not affected | n/a |
| Red Hat Enterprise Linux 6 | openssl | Not affected | n/a |
| Red Hat Enterprise Linux 6 | openssl098e | Not affected | n/a |
| Red Hat Enterprise Linux 7 | openssl | Not affected | n/a |
| Red Hat Enterprise Linux 7 | openssl098e | Not affected | n/a |
| Red Hat JBoss Enterprise Application Platform 6 | openssl | Not affected | n/a |
| Red Hat JBoss Enterprise Web Server 1 | openssl | Not affected | n/a |
| Red Hat JBoss Enterprise Web Server 2 | openssl | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Not vulnerable. This issue does not affect any version of the OpenSSL package as shipped with Red Hat Enterprise Linux 4, 5, 6 and 7, JBoss Enterprise Application Platform 6, Red Hat JBoss Enterprise Web Server 1 and 2, and Red Hat JBoss Web Server 3 because they did not include support for alternative certificate chains.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
AV:N/AC:L/Au:N/C:P/I:P/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (23 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 62.39% (0.62394) | 99.16th | v5 (v2026.06.15) |
| Sep 22, 2026 | 62.39% (0.62394) | 99.15th | v5 (v2026.06.15) |
| Sep 21, 2026 | 71.15% (0.71150) | 99.40th | v5 (v2026.06.15) |
| Sep 6, 2026 | 62.39% (0.62394) | 99.13th | v5 (v2026.06.15) |
| Sep 5, 2026 | 71.15% (0.71150) | 99.38th | v5 (v2026.06.15) |
| Aug 30, 2026 | 62.39% (0.62394) | 99.12th | v5 (v2026.06.15) |
| Aug 28, 2026 | 71.15% (0.71150) | 99.38th | v5 (v2026.06.15) |
| Aug 24, 2026 | 62.39% (0.62394) | 99.12th | v5 (v2026.06.15) |
| Aug 23, 2026 | 71.15% (0.71150) | 99.38th | v5 (v2026.06.15) |
| Jun 15, 2026 | 61.80% (0.61798) | 99.06th | v5 (v2026.06.15) |
| Mar 29, 2026 | 76.45% (0.76449) | 98.92th | v4 (v2025.03.14) |
| Feb 25, 2026 | 82.69% (0.82685) | 99.21th | v4 (v2025.03.14) |
| Dec 21, 2025 | 85.56% (0.85556) | 99.33th | v4 (v2025.03.14) |
| Aug 8, 2025 | 82.69% (0.82685) | 99.18th | v4 (v2025.03.14) |
| Apr 10, 2025 | 85.56% (0.85556) | 99.33th | v4 (v2025.03.14) |
| Mar 17, 2025 | 87.28% (0.87281) | 99.41th | v4 (v2025.03.14) |
| Dec 17, 2024 | 15.40% (0.15398) | 95.86th | v3 (v2023.03.01) |
| Sep 22, 2024 | 8.77% (0.08765) | 94.65th | v3 (v2023.03.01) |
| Jun 15, 2024 | 10.51% (0.10510) | 95.03th | v3 (v2023.03.01) |
| Nov 8, 2023 | 14.15% (0.14147) | 95.13th | v3 (v2023.03.01) |
| Mar 7, 2023 | 8.26% (0.08260) | 93.32th | v3 (v2023.03.01) |
| Mar 6, 2023 | 78.58% (0.78577) | 99.46th | v2 (v2022.01.01) |
| Feb 4, 2022 | 78.58% (0.78577) | 99.36th | v2 (v2022.01.01) |
References (35)
- http://fortiguard.com/advisory/2015-07-09-cve-2015-1793-openssl-alternative-chains-certificate-forgery x_refsource_CONFIRM
- http://ftp.netbsd.org/pub/NetBSD/security/advisories/NetBSD-SA2015-008.txt.asc vendor-advisoryx_refsource_NETBSD
- http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10694 x_refsource_CONFIRM
- http://lists.fedoraproject.org/pipermail/package-announce/2015-July/161747.html vendor-advisoryx_refsource_FEDORA
- http://lists.fedoraproject.org/pipermail/package-announce/2015-July/161782.html vendor-advisoryx_refsource_FEDORA
- http://marc.info/?l=bugtraq&m=143880121627664&w=2 vendor-advisoryx_refsource_HP
- http://marc.info/?l=bugtraq&m=144370846326989&w=2 vendor-advisoryx_refsource_HP
- http://openssl.org/news/secadv_20150709.txt x_refsource_CONFIRMVendor Advisory
- http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20150710-openssl vendor-advisoryx_refsource_CISCO
- http://www.fortiguard.com/advisory/2015-07-09-cve-2015-1793-openssl-alternative-chains-certificate-forgery x_refsource_CONFIRM
- http://www.oracle.com/technetwork/security-advisory/cpuapr2016v3-2985753.html x_refsource_CONFIRMPatch
- http://www.oracle.com/technetwork/security-advisory/cpujul2016-2881720.html x_refsource_CONFIRM
- http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html x_refsource_CONFIRM
- http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html x_refsource_CONFIRM
- http://www.oracle.com/technetwork/topics/security/bulletinjul2015-2511963.html x_refsource_CONFIRM
- http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html x_refsource_CONFIRMPatch
- http://www.oracle.com/technetwork/topics/security/cpuoct2015-2367953.html x_refsource_CONFIRMPatch
- http://www.securityfocus.com/bid/75652 vdb-entryx_refsource_BID
- http://www.securityfocus.com/bid/91787 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id/1032817 vdb-entryx_refsource_SECTRACK
- http://www.slackware.com/security/viewer.php?l=slackware-security&y=2015&m=slackware-security.561427 vendor-advisoryx_refsource_SLACKWARE
- http://www1.huawei.com/en/security/psirt/security-bulletins/security-advisories/hw-454058.htm x_refsource_CONFIRM
- https://access.redhat.com/security/cve/CVE-2015-1793 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1238619 Issue Tracking
- https://git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=9a0db453ba017ebcaccbee933ee6511a9ae4d1c8 x_refsource_CONFIRM
- https://h20564.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c04822825 x_refsource_CONFIRM
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05045763 x_refsource_CONFIRM
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05184351 x_refsource_CONFIRM
- https://help.ecostruxureit.com/display/public/UADCO8x/StruxureWare+Data+Center+Operation+Software+Vulnerability+Fixes x_refsource_CONFIRM
- https://kc.mcafee.com/corporate/index?page=content&id=SB10125 x_refsource_CONFIRM
- https://nvd.nist.gov/vuln/detail/CVE-2015-1793
- https://security.gentoo.org/glsa/201507-15 vendor-advisoryx_refsource_GENTOO
- https://www.cve.org/CVERecord?id=CVE-2015-1793
- https://www.exploit-db.com/exploits/38640/ exploitx_refsource_EXPLOIT-DB
- https://www.freebsd.org/security/advisories/FreeBSD-SA-15:12.openssl.asc vendor-advisoryx_refsource_FREEBSD
Change history (0)
No recorded changes yet.