CVE-2026-58150

Apache Traffic Server does not reject Transfer-Encoding in HTTP/2 requests, allowing downgrade request smuggling. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3. Users are recommended to upgrade to version 9.2.15 or 10.1.4...

GHSA-J92G-9F8W-J867 PostgreSQL JDBC Driver: Silent channel-binding authentication downgrade via unsupported certificate algorithms

Impact channelBinding=require connections can be silently downgraded from SCRAM-SHA-256-PLUS with channel binding to plain SCRAM-SHA-256 without it, losing the man-in-the-middle protection the setting is meant to guarantee. An attacker who can intercept the TLS connection triggers the downgrade...

CVE-2026-4942 IBM i is Affected by Algorithm Downgrade in Transport Layer Security []

IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to send a specifically crafted message and downgrade the Transport Layer Security TLS protocol to a version disabled in the server configuration...

JLSEC-2026-684 A malicious TLS1.2 server can force a TLS1.3 client with downgrade capability to use a ciphersuite...

A malicious TLS1.2 server can force a TLS1.3 client with downgrade capability to use a ciphersuite that it did not agree to and achieve a successful connection. This is because, aside from the extensions, the client was skipping fully parsing the server hello...

PYSEC-2026-1435 h2 allows HTTP Request Smuggling due to illegal characters in headers

Summary HTTP/2 request splitting vulnerability allows attackers to perform request smuggling attacks by injecting CRLF characters into headers. This occurs when servers downgrade HTTP/2 requests to HTTP/1.1 without properly validating header names/values, enabling attackers to manipulate request...

PYSEC-2026-1763 PDM Trojan Lockfile

Summary It's possible to craft a malicious pdm.lock file that could allow e.g. an insider or a malicious open source project to appear to depend on a trusted PyPI project, but actually install another project. Details Project foo can be targeted by creating the project foo-2 and uploading the fil...

CVE-2026-44937 SUSE Rancher Fleet had an Unauthenticated Webhook: Regex Injection via Unsanitized Repository URL Components

Potential forgery of webhook requests when using a unauthenticated webhook in SUSE Rancher Fleet 0.15 before 0.15.2, 0.14 before 0.14.6, 0.13 before 0.13.11 and 0.12 before 0.12.5 could be used by remote attackers to cause a denial of service or a downgrade attack on other repositories on the...

CVE-2026-44937

Potential forgery of webhook requests when using a unauthenticated webhook in SUSE Rancher Fleet 0.15 before 0.15.2, 0.14 before 0.14.6, 0.13 before 0.13.11 and 0.12 before 0.12.5 could be used by remote attackers to cause a denial of service or a downgrade attack on other repositories on the...

GHSA-P9JG-FCR6-3MHF OnGres SCRAM silent channel-binding authentication downgrade via unsupported certificate algorithms

Summary A flaw in com.ongres.scram:scram-client allows an attacker capable of performing a TLS man-in-the-middle MITM attack to silently downgrade a connection from SCRAM-SHA-256-PLUS with channel binding to standard SCRAM-SHA-256 without channel binding, bypassing strict client-side enforcement...

Not Failing Securely ('Failing Open')

Overview Affected versions of this package are vulnerable to Not Failing Securely 'Failing Open' in the TlsServerEndpoint process when a server presents an X.509 certificate using a modern signature algorithm lacking traditional naming structures. An attacker can bypass strict client-side...

Astra Linux – Vulnerability in Thunderbird

Thunderbird ignored the configuration that required STARTTLS security for SMTP connections. A MITM could perform a downgrade attack to intercept transmitted messages, or could take control of the authenticated session to execute SMTP commands chosen by the MITM. If an unprotected authentication...

CVE-2026-40594 pyLoad: Session Cookie Security Downgrade via Untrusted X-Forwarded-Proto Header Spoofing (Global State Race Condition)

pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev98, the setsessioncookiesecure beforerequest handler in src/pyload/webui/app/init.py reads the X-Forwarded-Proto header from any HTTP request without validating that the request originates from a trusted prox...

CVE-2026-26994

A flaw was found in uTLS. An active network attacker could exploit this vulnerability by manipulating the initial connection message ClientHello during the TLS handshake. This manipulation forces a downgrade from the more secure TLS 1.3 protocol to an older, less secure version like TLS 1.2. As a...

CVE-2026-26994

uTLS is a fork of crypto/tls, created to customize ClientHello for fingerprinting resistance while still using it for the handshake. In versions 1.6.7 and below, uTLS did not implement the TLS 1.3 downgrade protection mechanism specified in RFC 8446 Section 4.1.3 when using a uTLS ClientHello spe...

UBUNTU-CVE-2026-26994

uTLS is a fork of crypto/tls, created to customize ClientHello for fingerprinting resistance while still using it for the handshake. In versions 1.6.7 and below, uTLS did not implement the TLS 1.3 downgrade protection mechanism specified in RFC 8446 Section 4.1.3 when using a uTLS ClientHello spe...

CVE-2026-26994

uTLS is a fork of crypto/tls, created to customize ClientHello for fingerprinting resistance while still using it for the handshake. In versions 1.6.7 and below, uTLS did not implement the TLS 1.3 downgrade protection mechanism specified in RFC 8446 Section 4.1.3 when using a uTLS ClientHello spe...

uTLS 安全漏洞

uTLS is an open-source Go language codebase developed by Refraction Networking. Versions of uTLS 1.6.7 and earlier contain security vulnerabilities. These vulnerabilities stem from the lack of a TLS 1.3 downgrade protection mechanism, which could lead to connection downgrade attacks...

PT-2026-5906

Name of the Vulnerable Software and Affected Versions HCL AION version 2.0 Description HCL AION is susceptible to a missing or insecure HTTP Strict-Transport-Security HSTS header. This can permit insecure connections, potentially exposing the application to man-in-the-middle and protocol downgrad...

MiracleLinux 7 : samba-4.10.16-17.el7 (AXSA:2021-2787:06)

The remote MiracleLinux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the AXSA:2021-2787:06 advisory. samba: Active Directory AD domain user could become root on domain members CVE-2020-25717 samba: SMB1 client connections can be downgraded to...

MiracleLinux 7 : samba-4.2.3-11.el7 (AXSA:2016-023:01)

The remote MiracleLinux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the AXSA:2016-023:01 advisory. Samba is the standard Windows interoperability suite of programs for Linux and Unix. Security issues fixed with this release: CVE-2015-3223 The...