Common Weakness Enumeration
CWE-295
AllowedImproper Certificate Validation
Abstraction: Base · Status: Draft
The product does not validate, or incorrectly validates, a certificate.
2039 vulnerabilities reference this CWE, most recent first.
CVE-2026-45170 (GCVE-0-2026-45170)
Vulnerability from cvelistv5 – Published: 2026-06-12 00:05 – Updated: 2026-06-23 19:11
VLAI
EPSS
VEX
Title
Idira Vendor PAM - Self-Hosted Connector: Potential Security Bypass due to Incomplete TLS Certificate Validation
Summary
Idira Vendor PAM - Self-Hosted Connector versions prior 1.1.100504 under specific conditions and configuration scenarios, TLS certificate validation may not be fully enforced. CyberArk Security Bulletin: CA26-17
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-12 13:36 UTC
CWE
- CWE-295 - - Improper Certificate Validation
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://docs.cyberark.com/ | vendor-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| CyberArk Software, a Palo Alto Networks Company | Vendor PAM |
Affected:
1.1.0 , < 1.1.100504
(custom)
cpe:2.3:a:cyberark_software_a_palo_alto_networks_company:vendor_pam:*:*:*:*:*:*:*:* |
Date Public
2026-06-11 17:10
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CVE-2026-44900 (GCVE-0-2026-44900)
Vulnerability from cvelistv5 – Published: 2026-05-26 21:04 – Updated: 2026-05-28 14:12
VLAI
EPSS
VEX
Title
epa4all-client: VAU Signature bypass
Summary
epa4all-client is the Java Client for epa4all / ePA 3.0 in the Telematik Infrastruktur. Prior to 1.2.1, in SignedPublicKeysTrustValidatorImpl.isTrusted(), the ECDSA signature verification at line 45 discards the boolean return value of Signature.verify(). The method performs certificate chain validation, OCSP check, and signature algorithm setup, but never checks whether the signature actually matches. For any structurally valid signature, it returns true. This vulnerability is fixed in 1.2.1.
Severity
8.1 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-28 14:12 UTC
CWE
- CWE-295 - Improper Certificate Validation
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/oviva-ag/epa4all-client/securi… | x_refsource_CONFIRM |
| https://github.com/oviva-ag/epa4all-client/pull/34 | x_refsource_MISC |
Impacted products
2 products
| Vendor | Product | Version | |
|---|---|---|---|
| oviva-ag | epa4all-client |
Affected:
< 1.2.1
|
|
| com.oviva.telematik | epa4all-client |
Affected:
< 1.2.1
|
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CVE-2026-44700 (GCVE-0-2026-44700)
Vulnerability from cvelistv5 – Published: 2026-05-14 20:51 – Updated: 2026-05-15 11:22
VLAI
EPSS
VEX
Title
Elixir WebRTC: Missing DTLS peer fingerprint validation in ex_webrtc client-role handshake
Summary
Elixir WebRTC is an Elixir implementation of the W3C WebRTC API. Prior to 0.15.1 and 0.16.1, missing DTLS peer certificate fingerprint validation in the DTLS client (active) role removes one side of WebRTC's mutual authentication. The bug is not independently exploitable for media interception in standard deployments, but enables a full man-in-the-middle attack when chained with insecure signalling or a peer with similar validation gaps. This vulnerability is fixed in 0.15.1 and 0.16.1.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-15 11:22 UTC
CWE
- CWE-295 - Improper Certificate Validation
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://github.com/elixir-webrtc/ex_webrtc/securi… | x_refsource_CONFIRM |
| https://github.com/elixir-webrtc/ex_webrtc/issues/249 | x_refsource_MISC |
| https://github.com/elixir-webrtc/ex_webrtc/pull/250 | x_refsource_MISC |
| https://github.com/elixir-webrtc/ex_webrtc/releas… | x_refsource_MISC |
| https://github.com/elixir-webrtc/ex_webrtc/releas… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| elixir-webrtc | ex_webrtc |
Affected:
< 0.15.1
Affected: >= 0.16.0, < 0.16.1 |
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CVE-2026-44363 (GCVE-0-2026-44363)
Vulnerability from cvelistv5 – Published: 2026-05-13 19:16 – Updated: 2026-05-14 12:31
VLAI
EPSS
VEX
Title
Unsafe remote resource fetching in expansion misp-modules
Summary
MISP modules are autonomous modules that can be used to extend MISP for new services. Prior to 3.0.7, an unsafe remote resource fetching vulnerability existed in MISP Modules expansion modules. The html_to_markdown module accepted arbitrary HTTP(S) URLs without sufficient validation, which could allow Server-Side Request Forgery against loopback, private, or link-local network resources. Additionally, the qrcode module disabled TLS certificate verification when retrieving remote images, exposing requests to potential man-in-the-middle interception or response tampering. The issue was fixed by validating URL schemes, blocking local and private address ranges, resolving hostnames before fetching, enforcing request timeouts, and re-enabling TLS certificate verification. This vulnerability is fixed in 3.0.7.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-14 12:31 UTC
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/MISP/misp-modules/security/adv… | x_refsource_CONFIRM |
| https://github.com/MISP/misp-modules/commit/01a52… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| MISP | misp-modules |
Affected:
< 3.0.7
|
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CVE-2026-44312 (GCVE-0-2026-44312)
Vulnerability from cvelistv5 – Published: 2026-05-14 16:15 – Updated: 2026-05-15 18:05
VLAI
EPSS
VEX
Title
css_parser allows to MITM included https css urls
Summary
css_parser is a Ruby CSS parser. Prior to 2.1.0 and 1.22.0, the CSS Parser gem does not validate HTTPS connections, allowing a Man-in-the-Middle (MITM) attacker to inject or modify CSS content when stylesheets are loaded via HTTPS. The connection is established with OpenSSL::SSL::VERIFY_NONE, meaning any HTTPS certificate—even entirely untrusted—will be accepted without validation. This vulnerability is fixed in 2.1.0 and 1.22.0.
Severity
5.8 (Medium)
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-15 18:05 UTC
CWE
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/premailer/css_parser/security/… | x_refsource_CONFIRM |
| https://github.com/premailer/css_parser/issues/185 | x_refsource_MISC |
| https://github.com/premailer/css_parser/commit/35… | x_refsource_MISC |
| https://github.com/premailer/css_parser/commit/e0… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| premailer | css_parser |
Affected:
>= 2.0.0, < 2.1.0
Affected: < 1.22.0 |
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CVE-2026-44309 (GCVE-0-2026-44309)
Vulnerability from cvelistv5 – Published: 2026-05-15 16:22 – Updated: 2026-05-15 17:43
VLAI
EPSS
VEX
Title
gitsign verify accepts signatures over go-git-normalized bytes, enabling trust confusion on malformed commits
Summary
Gitsign is a keyless Sigstore to signing tool for Git commits with your a GitHub / OIDC identity. Prior to 0.16.0, gitsign verify and gitsign verify-tag re-encode commit/tag objects through go-git's EncodeWithoutSignature before checking the signature, instead of verifying against the raw git object bytes. For malformed objects with duplicate tree headers, git-core and go-git parse different trees: git-core uses the first, go-git uses the second. A signature crafted over the go-git-normalized form (second tree) passes gitsign verify while git-core resolves the commit to a completely different tree. This breaks the invariant that a verified signature, the commit semantics git-core presents to users, and the object hash logged in Rekor all refer to the same content. This vulnerability is fixed in 0.16.0.
Severity
5.3 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-15 17:43 UTC
CWE
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/sigstore/gitsign/security/advi… | x_refsource_CONFIRM |
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CVE-2026-44305 (GCVE-0-2026-44305)
Vulnerability from cvelistv5 – Published: 2026-05-12 21:28 – Updated: 2026-05-13 14:26
VLAI
EPSS
VEX
Title
Lemur: LDAP TLS certificate verification globally disabled enables credential interception
Summary
Lemur manages TLS certificate creation. Prior to 1.9.0, when LDAP TLS is enabled (LDAP_USE_TLS = True), Lemur's LDAP authentication module unconditionally disables TLS certificate verification at the global ldap module level. This allows a man-in-the-middle attacker positioned between Lemur and the LDAP server to intercept all authentication credentials. This vulnerability is fixed in 1.9.0.
Severity
6.8 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-13 14:26 UTC
CWE
- CWE-295 - Improper Certificate Validation
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/Netflix/lemur/security/advisor… | x_refsource_CONFIRM |
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CVE-2026-44213 (GCVE-0-2026-44213)
Vulnerability from cvelistv5 – Published: 2026-05-26 21:34 – Updated: 2026-05-27 15:51
VLAI
EPSS
VEX
Title
OpenTelemetry.Exporter.Instana bypasses TLS certificate validation when a proxy is configured
Summary
The OpenTelemetry.Exporter.Instana exports telemetry to Instana backend. Prior to 1.1.0, the OpenTelemetry.Exporter.Instana NuGet package does not validate HTTPS/TLS certificates are valid when sending telemetry to a configured Instana back-end when a proxy is configured using the INSTANA_ENDPOINT_PROXY environment variable. If a network attacker can Man-in-the-Middle (MitM) the proxy connection, all OpenTelemetry telemetry data and the Instana API key are exposed to the attacker. This vulnerability is fixed in 1.1.0.
Severity
6.5 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-27 15:50 UTC
CWE
- CWE-295 - Improper Certificate Validation
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/open-telemetry/opentelemetry-d… | x_refsource_CONFIRM |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| open-telemetry | opentelemetry-dotnet-contrib |
Affected:
< 1.1.0
|
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CVE-2026-42791 (GCVE-0-2026-42791)
Vulnerability from cvelistv5 – Published: 2026-05-27 12:23 – Updated: 2026-07-24 14:14
VLAI
EPSS
VEX
Title
OCSP responder certificate validity period not checked in public_key
Summary
Improper Certificate Validation vulnerability in Erlang OTP public_key (pubkey_ocsp module) allows forged OCSP responses signed with an expired responder certificate to be accepted as valid.
OCSP response verification in pubkey_ocsp:verify_response/5 and pubkey_ocsp:is_authorized_responder/3 in lib/public_key/src/pubkey_ocsp.erl does not check the validity period (notBefore/notAfter) of the OCSP responder certificate. An attacker who has obtained the private key of an expired CA-designated OCSP responder certificate can forge OCSP responses that Erlang/OTP accepts as valid.
This affects TLS clients using OCSP stapling via the ssl application: a malicious or compromised server can present a revoked TLS certificate together with a forged OCSP response signed by an expired responder key, and the client will accept the revoked certificate as valid. It also affects applications calling public_key:pkix_ocsp_validate/5 directly, where the impact depends on the use case — server-side client certificate validation using this API may allow authentication bypass with a revoked client certificate.
This issue affects OTP from OTP 27.0 before OTP 29.0.1, OTP 28.5.0.1 and OTP 27.3.4.12, corresponding to public_key from 1.16 before 1.21.1, 1.20.3.1 and 1.17.1.3.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-27 15:40 UTC
CWE
Assigner
References
6 references
| URL | Tags |
|---|---|
| https://github.com/erlang/otp/security/advisories… | vendor-advisoryrelated |
| https://cna.erlef.org/cves/CVE-2026-42791.html | related |
| https://osv.dev/vulnerability/EEF-CVE-2026-42791 | related |
| https://www.erlang.org/doc/system/versions.html#o… | x_version-scheme |
| https://github.com/erlang/otp/commit/7995f1fdaee3… | patch |
| https://github.com/erlang/otp/commit/b3870e02405c… | patch |
Impacted products
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CVE-2026-42790 (GCVE-0-2026-42790)
Vulnerability from cvelistv5 – Published: 2026-05-27 15:09 – Updated: 2026-08-14 12:04
VLAI
EPSS
VEX
Title
nameConstraints DNS bypass via subject CommonName fallback in public_key hostname verification
Summary
Improper Certificate Validation vulnerability in Erlang OTP public_key (pubkey_cert and public_key modules) allows a DNS nameConstraints bypass via subject CommonName fallback in TLS hostname verification.
Two flaws combine to allow a subordinate CA whose DNS nameConstraints are restricted (e.g. permitted;DNS:allowed.example.com) to issue a leaf certificate that an OTP TLS client accepts as a valid identity for an out-of-scope hostname (e.g. victim.example.com):
First, pubkey_cert:validate_names/6 in lib/public_key/src/pubkey_cert.erl only checks SAN DNS entries against nameConstraints. Per RFC 5280, a permitted DNS subtree only restricts certificates that contain a DNS-typed name. A leaf with no subjectAltName therefore trivially satisfies any permitted;DNS:... constraint regardless of its subject commonName.
Second, public_key:pkix_verify_hostname/3 in lib/public_key/src/public_key.erl falls back to the subject commonName when no subjectAltName is present, extracting id-at-commonName attributes as presented IDs and matching them against the reference hostname. The strict pkix_verify_hostname_match_fun(https) matcher does not suppress this fallback.
The result is that path validation accepts a CN-only leaf under a DNS-constrained intermediate (no SAN means the nameConstraints are not triggered), and hostname verification then accepts it via the CN fallback. The bypass is reachable from stock ssl:connect with verify_peer, a trusted CA, SNI, and the canonical strict https hostname matcher.
This issue affects OTP from OTP 19.3 before OTP 29.0.1, OTP 28.5.0.1, OTP 27.3.4.12 and OTP 26.2.5.21, corresponding to public_key from 1.4 before 1.21.1, 1.20.3.1, 1.17.1.3 and 1.15.1.7.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-27 00:00 UTC
CWE
Assigner
References
12 references
| URL | Tags |
|---|---|
| https://github.com/erlang/otp/security/advisories… | vendor-advisoryrelated |
| https://cna.erlef.org/cves/CVE-2026-42790.html | related |
| https://osv.dev/vulnerability/EEF-CVE-2026-42790 | related |
| https://www.erlang.org/doc/system/versions.html#o… | x_version-scheme |
| https://github.com/erlang/otp/commit/0769050c69d7… | patch |
| https://github.com/erlang/otp/commit/fb67c6d1836f… | patch |
| https://github.com/erlang/otp/commit/21abed64eb20… | patch |
| https://access.redhat.com/security/cve/CVE-2026-42790 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2482286 | issue-trackingx_refsource_REDHAT |
| https://security.access.redhat.com/data/csaf/v2/v… | x_sadp-csaf-vex |
| https://access.redhat.com/errata/RHSA-2026:54757 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:39809 | vendor-advisoryx_refsource_REDHAT |
Impacted products
5 products
| Vendor | Product | Version | |
|---|---|---|---|
| Erlang | OTP |
Affected:
1.4 , < *
(otp)
cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:* |
|
| Erlang | OTP |
Affected:
19.3 , < *
(otp)
Affected: b0c245e8132bb13171e277b1af59c0cec00c9459 , < * (git) cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:* |
|
| Red Hat | Red Hat OpenStack Platform 16.2 |
Unaffected:
0:23.3.4.18-2.el8ost , < *
(rpm)
cpe:/a:redhat:openstack:16.2::el8 |
|
| Red Hat | Red Hat OpenStack Services on OpenShift 18.0 |
Unaffected:
0:26.2.5.21-2.el9ost , < *
(rpm)
cpe:/a:redhat:openstack:18.0::el9 |
|
| Red Hat | Red Hat OpenStack Platform 17.1 |
cpe:/a:redhat:openstack:17.1
|
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"value": "Reported to Red Hat."
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"value": "Ensure all TLS certificates used in the deployment include Subject Alternative Name (SAN) extensions with the appropriate DNS entries. Certificates relying solely on the CommonName (CN) field for hostname identification are susceptible to this bypass. For Erlang applications, the verify_fun option in the ssl module can be configured to reject peer certificates missing the subjectAltName extension."
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Mitigation
Architecture and Design
Implementation
Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
Mitigation
Implementation
If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.
CAPEC-459: Creating a Rogue Certification Authority Certificate
An adversary exploits a weakness resulting from using a hashing algorithm with weak collision resistance to generate certificate signing requests (CSR) that contain collision blocks in their "to be signed" parts. The adversary submits one CSR to be signed by a trusted certificate authority then uses the signed blob to make a second certificate appear signed by said certificate authority. Due to the hash collision, both certificates, though different, hash to the same value and so the signed blob works just as well in the second certificate. The net effect is that the adversary's second X.509 certificate, which the Certification Authority has never seen, is now signed and validated by that Certification Authority.
CAPEC-475: Signature Spoofing by Improper Validation
An adversary exploits a cryptographic weakness in the signature verification algorithm implementation to generate a valid signature without knowing the key.