CVE-2026-54275

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, the serverhostname TLS SNI check can be bypassed when an existing connection is reused. If an application makes multiple requests to the same domain, but with different per-request serverhostname...

CVE-2026-54275 AIOHTTP: TLS Server Hostname Override Is Ignored When Reusing HTTPS Connections

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, the serverhostname TLS SNI check can be bypassed when an existing connection is reused. If an application makes multiple requests to the same domain, but with different per-request serverhostname...

PT-2026-50163

Name of the Vulnerable Software and Affected Versions Traefik versions 3.6.17 through 3.7.1 Description An issue in the HTTP/3 QUIC TLS configuration selection allows unauthenticated clients to bypass router-specific mutual TLS mTLS enforcement. When HTTP/3 is enabled, the TLS handshake uses an...

aiohttp: TLS Server Hostname Override Is Ignored When Reusing HTTPS Connections

Summary The serverhostname TLS SNI check can be bypassed when an existing connection is reused. Impact If an application makes multiple requests to the same domain, but with different per-request serverhostname parameters, then the later calls may succeed by reusing the existing connection when...

FreeBSD : h2o -- heap overrun parsing zero-length SNI (fba766f4-ccda-4e1b-8875-ab857c6a6532)

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the fba766f4-ccda-4e1b-8875-ab857c6a6532 advisory. h2o project reports: When h2o receives a TLS or QUIC ClientHello containing a zero-length SNI extension...

CVE-2026-5503

In TLSXEchChangeSNI, the ctx-extensions branch set extensions unconditionally even when TLSXFind returned NULL. This caused TLSXUseSNI to attach the attacker-controlled publicName to the shared WOLFSSLCTX when no inner SNI was configured. TLSXEchRestoreSNI then failed to clean it up because its...

h2o -- heap overrun parsing zero-length SNI

h2o project reports: When h2o receives a TLS or QUIC ClientHello containing a zero-length SNI extension, it can overrun the zero-length hostname while copying it. This can trigger a segmentation fault and cause a denial of service...

Unity Linux 20.1060e / 20.1070e Security Update: lynx (UTSA-2026-016667)

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-016667 advisory. Lynx through 2.8.9 mishandles the userinfo subcomponent of a URI, which allows remote attackers to discover cleartext credentials because they may appear in SNI data...

Security Bulletin: Multiple Vulnerabilities in pyOpenSSL bundled with IBM Fusion, IBM Fusion HCI, and IBM Fusion Data Cataloging

Summary IBM Fusion, IBM Fusion HCI, and IBM Fusion Data Cataloging include the pyOpenSSL library, which is susceptible to a critical buffer overflow and a "fail-open" security bypass. A classic buffer overflow vulnerability exists when a user-provided cookie generation callback returns a value...

Vert.x has a DoS via unbounded server-side SNI SslContext cache growth

Potential unbounded server-side SNI SslContext cache growth in Vert.x TLS handling, with = resource-exhaustion / DoS impact. On affected versions, matching server-side SNI names are cached via computeIfAbsentserverName, ... in a serverName-keyed SslContext cache. The implementation differs slight...

Astra Linux – Vulnerability in Tomcat9

Improper input validation vulnerability. This issue affects Apache Tomcat: versions 11.0.0-M1 through 11.0.14, 10.1.0-M1 through 10.1.49, and 9.0.0-M1 through 9.0.112. The following versions were at the end of their support lifecycles at the time the CVE was created, but are still affected: 8.5.0...

tomcat: Client certificate verification bypass due to virtual host mapping

A certificate validation flaw has been found in Apache Tomcat. omcat did not validate that the host name provided via the SNI extension was the same as the host name provided in the HTTP host header field. If Tomcat was configured with more than one virtual host and the TLS configuration for one ...

Linux Distros Unpatched Vulnerability : CVE-2026-5503

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - In TLSXEchChangeSNI, the ctx-extensions branch set extensions unconditionally even when TLSXFind returned NULL. This caused TLSXUseSNI to attach the...

CVE-2026-5503

In TLSXEchChangeSNI, the ctx-extensions branch set extensions unconditionally even when TLSXFind returned NULL. This caused TLSXUseSNI to attach the attacker-controlled publicName to the shared WOLFSSLCTX when no inner SNI was configured. TLSXEchRestoreSNI then failed to clean it up because its...

DEBIAN-CVE-2026-5503

In TLSXEchChangeSNI, the ctx-extensions branch set extensions unconditionally even when TLSXFind returned NULL. This caused TLSXUseSNI to attach the attacker-controlled publicName to the shared WOLFSSLCTX when no inner SNI was configured. TLSXEchRestoreSNI then failed to clean it up because its...

CVE-2026-5503

In TLSXEchChangeSNI, the ctx-extensions branch set extensions unconditionally even when TLSXFind returned NULL. This caused TLSXUseSNI to attach the attacker-controlled publicName to the shared WOLFSSLCTX when no inner SNI was configured. TLSXEchRestoreSNI then failed to clean it up because its...

CVE-2026-5503

In TLSXEchChangeSNI, the ctx-extensions branch set extensions unconditionally even when TLSXFind returned NULL. This caused TLSXUseSNI to attach the attacker-controlled publicName to the shared WOLFSSLCTX when no inner SNI was configured. TLSXEchRestoreSNI then failed to clean it up because its...

CVE-2026-5503

In TLSXEchChangeSNI, the ctx-extensions branch set extensions unconditionally even when TLSXFind returned NULL. This caused TLSXUseSNI to attach the attacker-controlled publicName to the shared WOLFSSLCTX when no inner SNI was configured. TLSXEchRestoreSNI then failed to clean it up because its...

CVE-2026-5503

In TLSXEchChangeSNI, the ctx-extensions branch set extensions unconditionally even when TLSXFind returned NULL. This caused TLSXUseSNI to attach the attacker-controlled publicName to the shared WOLFSSLCTX when no inner SNI was configured. TLSXEchRestoreSNI then failed to clean it up because its...

wolfSSL（CyaSSL） 安全漏洞

wolfSSL CyaSSL is a small, portable embedded SSL programming library developed by the US company wolfSSL, designed for developers working with embedded systems. wolfSSL CyaSSL contains a security vulnerability; this vulnerability stems from the TLSXEchChangeSNI function setting extensions...