Improper Certificate Validation

Fleet is open source device management software. Prior to version 4.81.0, a vulnerability in Fleet’s Windows MDM management endpoint could allow requests to be processed without proper client certificate validation. In certain circumstances, this could allow an attacker to impersonate an enrolled Windows device and retrieve sensitive configuration data. Fleet’s Windows MDM management endpoint relies on mutual TLS (mTLS) client certificates to authenticate enrolled devices. In affected versions, requests that did not present a client certificate could be incorrectly treated as trusted. As a result, an attacker with prior knowledge of a valid enrolled device identifier could potentially impersonate that device and receive configuration payloads intended for it. These payloads may contain sensitive information such as Wi-Fi or VPN configuration data, certificates, or other secrets delivered through MDM profiles. This issue does not allow enrollment of new devices, administrative access to Fleet, or compromise of the Fleet control plane. Impact is limited to the targeted Windows device. Version 4.81.0 contains a patch. If an immediate upgrade is not possible, affected Fleet users should temporarily disable Windows MDM.Show less

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.Show less

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.Show less

CKAN is an open-source DMS (data management system) for powering data hubs and data portals. Prior to 2.10.10 and 2.11.5, the configured SMTP server may be spoofed with any certificate (e.g. self-signed), leaving credentials and all emails sent open to MITM attacks. This vulnerability is fixed in 2.10.10 and 2.11.5.Show less

Multiple improper certificate validation vulnerabilities in the Palo Alto Networks GlobalProtect™ app enables an attacker to intercept encrypted communications and potentially compromise the endpoint. This can enable a local non-administrative operating system user or an attacker on the same subnet to redirect traffic to an unauthorized server and facilitate the installation of malicious software. The GlobalProtect app on Linux, Windows, iOS and GlobalProtect UWP app are not affected.Show less

An improper certificate validation vulnerability in the Prisma Access Agent® for Android and Chrome OS enables an attacker to perform a man-in-the-middle (MitM) attack to intercept VPN traffic. By presenting a certificate for any domain issued by a trusted Certificate Authority, the attacker can capture sensitive device information. The Prisma Access Agent on macOS, Windows, Linux and iOS are not affected.Show less

aria2c accepts a server certificate with incorrect Extended Key Usage (EKU). If the attackers compromise a certificate (with the associated private key) issued for a different purpose, they may be able to reuse it for TLS server authentication.Show less

When curl is told to use the Certificate Status Request TLS extension, often referred to as *OCSP stapling*, to verify that the server certificate is valid, it fails to detect OCSP problems and instead wrongly consider the response as fine.Show less

A vulnerability exists where a connection requiring TLS incorrectly reuses an existing unencrypted connection from the same connection pool. If an initial transfer is made in clear-text (via IMAP, SMTP, or POP3), a subsequent request to that same host bypasses the TLS requirement and instead transmit data unencrypted.Show less

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.Show less

"Kura Sushi Official App" provided by EPG, Inc. is vulnerable to improper certificate validation. A man-in-the-middle attack may allow eavesdropping on, or altering, the communication on push notifications between the affected application and the relevant server.Show less

pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev100, the set_config_value() API method (@permission(Perms.SETTINGS)) in src/pyload/core/api/__init__.py gates security-sensitive options behind a hand-maintained allowlist ADMIN_ONLY_CORE_OPTIONS. The option ("general", "ssl_verify") is not on that allowlist. Any authenticated user with the non-admin SETTINGS permission can set general.ssl_verify = off, and every subsequent outbound pycurl request is made with SSL_VERIFYPEER=0 and SSL_VERIFYHOST=0 — TLS peer and hostname verification are fully disabled. An on-path attacker can then present forged certificates for any hostname pyload fetches. This is a direct continuation of the fix family CVE-2026-33509 / CVE-2026-35463 / CVE-2026-35464 / CVE-2026-35586, each of which patched a different missed option in the same allowlist. This vulnerability is fixed in 0.5.0b3.dev100.Show less

SolidCAM-GPPL-IDE is an unofficial, independently developed extension, Postprocessor IDE for SolidCAM. From version 1.0.0 to before version 1.0.2, the inc "filename" directive in GPPL postprocessor files is resolved by GpplDocumentLinkHandler into a clickable link (VS Code textDocument/documentLink). The handler accepted arbitrary paths — absolute, relative with parent-directory segments (..\..\..\), UNC (\\server\share\), and arbitrary subfolders — and called File.Exists on each to decide whether to render the link. Two distinct attack surfaces resulted: information disclosure via File.Exists probing and NTLM hash leak via UNC path probing. This issue has been patched in version 1.0.2.Show less

PJSIP is a free and open source multimedia communication library written in C. Prior to version 2.17, on GnuTLS builds, the SIP TLS transport (sip_transport_tls) can accept connections with invalid or untrusted certificates even when the application explicitly enables certificate verification via verify_server = PJ_TRUE or verify_client = PJ_TRUE. This issue has been patched in version 2.17.Show less

Improper certificate validation in Ivanti EPMM before versions 12.6.1.1, 12.7.0.1, and 12.8.0.1 allows a remote unauthenticated attacker to enroll a device belonging to a restricted set of unenrolled devices, leading to information disclosure about EPMM appliance and impacting on the integrity of the newly enrolled device identity.Show less

An Improper Certificate Validation in Ivanti EPMM before versions 12.6.1.1, 12.7.0.1, and 12.8.0.1 allows a remote unauthenticated attacker to impersonate registered Sentry hosts and obtain valid CA-signed client certificates.Show less

A flaw was found in gnutls. This vulnerability occurs because permitted name constraints were incorrectly ignored when previous Certificate Authorities (CAs) only had excluded name constraints. A remote attacker could exploit this to bypass critical name constraint checks during certificate validation. This bypass could lead to the acceptance of invalid certificates, potentially enabling spoofing or man-in-the-middle attacks against affected systems.Show less

Incus is a system container and virtual machine manager. In versions before 7.0.0, broken TLS validation logic in the OVN database connection logic can allow connections to an attacker's OVN database. The OVN client implementations disable Go standard TLS server verification and replace it with custom peer-certificate verification logic. That replacement verifier does not anchor trust in the configured CA certificate. Instead, it constructs the verification root set from certificates supplied by the peer during the handshake, so the configured CA is parsed but not used as the trust anchor for the final verification decision. In OVN-enabled deployments that use these SSL database connection paths, an attacker able to impersonate or intercept the OVN endpoint on the management network can present a rogue self-signed certificate chain, and Incus will accept this certificate as valid. This issue defeats the intended CA-based trust model for OVN database connections and permits endpoint impersonation by an active attacker in a suitable network position. This issue is fixed in version 7.0.0.Show less