Ubuntu 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS : GnuTLS vulnerabilities (USN-8284-1)

The remote Ubuntu 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8284-1 advisory. Joshua Rogers discovered that GnuTLS did not properly handle malformed DTLS handshake fragments in certain cases. A remot...

crypto/x509: golang: Go crypto/x509: Certificate validation bypass due to incorrect DNS constraint application

A flaw was found in the crypto/x509 package within Go golang. When verifying a certificate chain, excluded DNS Domain Name System constraints are not correctly applied to wildcard DNS Subject Alternative Names SANs if the case of the SAN differs from the constraint. This oversight could allow an...

crypto/x509: golang: Go crypto/x509: Denial of Service via inefficient certificate chain validation

A flaw was found in Go's crypto/x509 package. A remote attacker could exploit this by presenting a specially crafted certificate chain containing a large number of policy mappings. This inefficient validation process consumes excessive resources, which can lead to a denial of service DoS for...

crypto/x509: golang: Go crypto/x509: Certificate validation bypass due to incorrect DNS constraint application

A flaw was found in the crypto/x509 package within Go golang. When verifying a certificate chain, excluded DNS Domain Name System constraints are not correctly applied to wildcard DNS Subject Alternative Names SANs if the case of the SAN differs from the constraint. This oversight could allow an...

crypto/x509: golang: Go crypto/x509: Denial of Service via inefficient certificate chain validation

A flaw was found in Go's crypto/x509 package. A remote attacker could exploit this by presenting a specially crafted certificate chain containing a large number of policy mappings. This inefficient validation process consumes excessive resources, which can lead to a denial of service DoS for...

Important: Red Hat Security Advisory: opentelemetry-collector security update

An update for opentelemetry-collector is now available for Red Hat Enterprise Linux 9.4 Extended Update Support. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System CVSS base score, which gives a detailed severity rating, ...

crypto/x509: golang: Go crypto/x509: Certificate validation bypass due to incorrect DNS constraint application

A flaw was found in the crypto/x509 package within Go golang. When verifying a certificate chain, excluded DNS Domain Name System constraints are not correctly applied to wildcard DNS Subject Alternative Names SANs if the case of the SAN differs from the constraint. This oversight could allow an...

crypto/x509: golang: Go crypto/x509: Denial of Service via inefficient certificate chain validation

A flaw was found in Go's crypto/x509 package. A remote attacker could exploit this by presenting a specially crafted certificate chain containing a large number of policy mappings. This inefficient validation process consumes excessive resources, which can lead to a denial of service DoS for...

Security Bulletin: IBM Guardium Data Protection is affected by multiple vulnerabilities

Summary IBM Guardium Data Protection has addressed these vulnerabilities in an update. Vulnerability Details CVEID:CVE-2025-61726 DESCRIPTION: The net/url package does not set a limit on the number of query parameters in a query. While the maximum size of query parameters in URLs is generally...

OSEC-2026-07 TLS-server does insufficient client certificate checks (missing KeyUsage and ExtendedKeyUsage validation)

The TLS server implementation does not validate the KeyUsage and ExtendedKeyUsage extensions of client certificates when mutually authenticated TLS is requested. This can lead to impersonation with a certificate issued to a server. Scenario An operations engineer enables mTLS on the admin endpoin...

crypto/tls: crypto/tls: Incorrect certificate validation during TLS session resumption

A flaw was found in the crypto/tls component. This vulnerability occurs during Transport Layer Security TLS session resumption when certificate authority CA settings are modified between the initial and resumed handshakes. An attacker could exploit this to bypass certificate validation, allowing ...

crypto/tls: crypto/tls: Incorrect certificate validation during TLS session resumption

A flaw was found in the crypto/tls component. This vulnerability occurs during Transport Layer Security TLS session resumption when certificate authority CA settings are modified between the initial and resumed handshakes. An attacker could exploit this to bypass certificate validation, allowing ...

USN-8284-1 gnutls28 vulnerabilities

Joshua Rogers discovered that GnuTLS did not properly handle malformed DTLS handshake fragments in certain cases. A remote attacker could possibly use this issue to obtain sensitive information, or cause a denial of service. CVE-2026-33845 Haruto Kimura, Oscar Reparaz, and Zou Dikai discovered th...

crypto/tls: crypto/tls: Incorrect certificate validation during TLS session resumption

A flaw was found in the crypto/tls component. This vulnerability occurs during Transport Layer Security TLS session resumption when certificate authority CA settings are modified between the initial and resumed handshakes. An attacker could exploit this to bypass certificate validation, allowing ...

Astra Linux – Vulnerability in qt4-x11, qtbase-opensource-src

A issue was discovered in Qt before version 5.15.15, in versions 6.x before 6.2.9, and in versions 6.3.x through 6.5.x before 6.5.2. Certificate validation for TLS does not always consider whether the root of a chain is a configured CA certificate...

Astra Linux – Vulnerability in Apache Log4j2

Improper validation of certificates with host mismatches in the Apache Log4j SMTP appender. This could allow an SMTPS connection to be intercepted by a man-in-the-middle attack, thereby leaking any log messages sent through that appender. This issue has been fixed in Apache Log4j 2.12.3 and 2.13....

Astra Linux – Vulnerability in Bouncycastle

The Bouncy Castle For Java version prior to 1.74 is affected by an LDAP injection vulnerability. This vulnerability only affects applications that use the LDAP CertStore provided by Bouncy Castle to validate X.509 certificates. During the certificate validation process, Bouncy Castle inserts the...

Astra Linux – Vulnerability in Thunderbird, Firefox

When using Alt-Svc, ALPN failed to properly validate certificates when the original server was redirecting to an insecure site. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6...

Astra Linux – Vulnerability in Heimdal

Heimdal is an implementation of ASN.1/DER, PKIX, and Kerberos. Versions prior to 7.7.1 are vulnerable to a denial-of-service vulnerability in Heimdal’s PKI certificate validation library. This vulnerability affects the KDC via PKINIT and kinit via PKINIT, as well as any third-party applications...

Astra Linux – Vulnerability in LibreOffice

LibreOffice supports digital signatures for ODF documents and macros within documents. It provides visual aids to indicate that the document has not been altered since the last signature, and that the signature is valid. A vulnerability in certificate validation in LibreOffice allowed attackers t...