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
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.
Noroxi analysis
No Noroxi analysis for this record yet
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We use this product, ask for help- Published
- Jul 9, 2015
- Updated
- Jun 16, 2026
- EPSS
- 62.4% · 99th percentile
- CWE
- CWE-254
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Report tools
Action score
45
Plan
Add it to your regular patch cycle.
- CVSS
- 26 / 40 · 6.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 19 / 30 · 62.4%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| openssl | openssl | cpe:2.3:a:openssl:openssl |
| oracle | supply chain products suite | cpe:2.3:a:oracle:supply_chain_products_suite |
| oracle | jd edwards enterpriseone tools | cpe:2.3:a:oracle:jd_edwards_enterpriseone_tools |
| oracle | opus 10g ethernet switch family | cpe:2.3:o:oracle:opus_10g_ethernet_switch_family |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- openssl openssl1.0.1n
- openssl openssl1.0.1o
- openssl openssl1.0.2b
- openssl openssl1.0.2c
- oracle jd edwards enterpriseone tools9.1
- oracle jd edwards enterpriseone tools9.2
- oracle opus 10g ethernet switch familyup to 2.0.0.6 inclusive
- oracle supply chain products suite6.1.2.2
- oracle supply chain products suite6.1.3.0
- oracle supply chain products suite6.2.0
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | openssl | before 1.0.2d-1 | 1.0.2d-1 |
| SUSE:Linux Enterprise Software Development Kit 11 SP3 | mysql | before 5.5.46-0.14.1 | 5.5.46-0.14.1 |
Same product
openssl: all recordsOther highest-scoring records for the same primary product.
- CVE-2014-0160The (1) TLS and (2) DTLS implementations in OpenSSL 1.0.1 before 1.0.1g do not properly handle Heartbeat Extension packets, which allows remKEV90Now
- CVE-2021-3711SM2 Decryption Buffer Overflow65This week
- CVE-2003-0545Double free vulnerability in OpenSSL 0.9.7 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code 65This week
- CVE-2016-2108The ASN.1 implementation in OpenSSL before 1.0.1o and 1.0.2 before 1.0.2c allows remote attackers to execute arbitrary code or cause a denia62This week
- CVE-2016-6309statem/statem.c in OpenSSL 1.1.0a does not consider memory-block movement after a realloc call, which allows remote attackers to cause a den60This week
- CVE-2022-3786X.509 Email Address Variable Length Buffer Overflow58Plan
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:openssl | 1.0.2d-1 · Debian:12 | Package registry (OSV) |
| suse:mysql | 5.5.46-0.14.1 · SUSE:Linux Enterprise Software Development Kit 11 SP3 | Package registry (OSV) |
Exploit status
Weaponized
A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.
Evidence
- Metasploit module ×1
- Exploit-DB entry ×1
Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.
| Source | Kind | Date |
|---|---|---|
| Exploit-DB entry | webapps | 2015-11-05 |
| Metasploit module | auxiliary/server/openssl_altchainsforgery_mitm_proxyOpenSSL Alternative Chains Certificate Forgery MITM Proxyauxiliary | 2015-07-09 |
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Metasploit-1 d
- Published
- First PoC+118 d
- TodaySep 30, 2026+4101 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- low · data can be read
- Integrity
- low · data or configuration can be modified
- Availability
- none
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- Low
- Integrity impact
- Low
- Availability impact
- None
Weakness class (CWE)
CWE-254 · 7PK - Security FeaturesCVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- fortiguard.com/advisory/2015-07-09-cve-2015-1793-openssl-alternative-chains-certificate-forgery
- ftp.netbsd.org/pub/NetBSD/security/advisories/NetBSD-SA2015-008.txt.asc
- kb.juniper.net/InfoCenter/index?page=content&id=JSA10694
- lists.fedoraproject.org/pipermail/package-announce/2015-July/161747.html
- lists.fedoraproject.org/pipermail/package-announce/2015-July/161782.html
- marc.info/?l=bugtraq&m=143880121627664&w=2
- marc.info/?l=bugtraq&m=144370846326989&w=2
- openssl.org/news/secadv_20150709.txt
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20150710-openssl
- www.fortiguard.com/advisory/2015-07-09-cve-2015-1793-openssl-alternative-chains-certificate-forgery
- www.oracle.com/technetwork/security-advisory/cpuapr2016v3-2985753.html
- www.oracle.com/technetwork/security-advisory/cpujul2016-2881720.html
- www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html
- www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
- www.oracle.com/technetwork/topics/security/bulletinjul2015-2511963.html
- www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html
- www.oracle.com/technetwork/topics/security/cpuoct2015-2367953.html
- www.securityfocus.com/bid/75652
- www.securityfocus.com/bid/91787
- www.securitytracker.com/id/1032817
Vendor advisories and official records. Exploit/PoC links are deliberately left out.