CVE-2026-16047 Board channel linking without read channel permission validation

Mattermost versions 11.7.x = 11.7.6, 10.11.x = 10.11.21, 11.8.x = 11.8.3 fail to validate that users have read access to a channel before linking a board to it, which allows an authenticated attacker to discover the membership of private channels on the same team via creating, patching, importing...

CVE-2026-16047

Mattermost versions 11.7.x = 11.7.6, 10.11.x = 10.11.21, 11.8.x = 11.8.3 fail to validate that users have read access to a channel before linking a board to it, which allows an authenticated attacker to discover the membership of private channels on the same team via creating, patching, importing...

CVE-2026-16047

Mattermost versions 11.7.x ≤ 11.7.6, 10.11.x ≤ 10.11.21, and 11.8.x ≤ 11.8.3 contain an authorization flaw in the board-to-channel linking functionality. The server fails to verify that the requesting user has read access to a target channel before associating a board with it. An authenticated us...

CVE-2026-74900

opensslencrypt versions before 1.4.0 contain a critical vulnerability in pqc.py where KEM decapsulation failures silently fall back to simulation mode, generating a deterministic shared secret from only 16 bytes of the private key and publicly available encapsulated key data. Attackers who obtain...

CVE-2026-74882

opensslencrypt versions before 1.4.0 contain an insecure default configuration that trusts the entire RFC 1918 private address space in IntegrityProxyConfig trustedproxies. Attackers on private networks can forge client certificate headers to bypass mTLS authentication when ProxyAuth validation i...

CVE-2026-74869

stoatchat before 0.15.0 contains a missing authorization vulnerability in the Subscribe message handler that allows authenticated attackers to enumerate members and monitor profile updates of private servers without membership. Attackers can subscribe to any server's member-update topic by sendin...

CVE-2026-74900 openssl_encrypt before 1.4.0 Weak Shared Secret via PQC Simulation Mode

opensslencrypt versions before 1.4.0 contain a critical vulnerability in pqc.py where KEM decapsulation failures silently fall back to simulation mode, generating a deterministic shared secret from only 16 bytes of the private key and publicly available encapsulated key data. Attackers who obtain...

CVE-2026-74900

openssl_encrypt before version 1.4.0 has a flaw in pqc.py: when KEM decapsulation fails, it silently falls back to simulation mode, deriving a deterministic shared secret from just 16 bytes of the private key plus public encapsulated key data. An attacker with those 16 private-key bytes can compu...

CVE-2026-74882 openssl_encrypt before 1.4.0 Insecure Default Configuration

opensslencrypt versions before 1.4.0 contain an insecure default configuration that trusts the entire RFC 1918 private address space in IntegrityProxyConfig trustedproxies. Attackers on private networks can forge client certificate headers to bypass mTLS authentication when ProxyAuth validation i...

EUVD-2026-60101

opensslencrypt versions before 1.4.0 contain an insecure default configuration that trusts the entire RFC 1918 private address space in IntegrityProxyConfig trustedproxies. Attackers on private networks can forge client certificate headers to bypass mTLS authentication when ProxyAuth validation i...

CVE-2026-74882 openssl_encrypt before 1.4.0 Insecure Default Configuration

opensslencrypt versions before 1.4.0 contain an insecure default configuration that trusts the entire RFC 1918 private address space in IntegrityProxyConfig trustedproxies. Attackers on private networks can forge client certificate headers to bypass mTLS authentication when ProxyAuth validation i...

CVE-2026-74882

opensslencrypt versions before 1.4.0 contain an insecure default configuration that trusts the entire RFC 1918 private address space in IntegrityProxyConfig trustedproxies. Attackers on private networks can forge client certificate headers to bypass mTLS authentication when ProxyAuth validation i...

CVE-2026-74869 stoatchat before 0.15.0 Missing Authorization via Subscribe

stoatchat before 0.15.0 contains a missing authorization vulnerability in the Subscribe message handler that allows authenticated attackers to enumerate members and monitor profile updates of private servers without membership. Attackers can subscribe to any server's member-update topic by sendin...

CVE-2026-74869

stoatchat before 0.15.0 contains a missing authorization vulnerability in the Subscribe message handler that allows authenticated attackers to enumerate members and monitor profile updates of private servers without membership. Attackers can subscribe to any server's member-update topic by sendin...

CVE-2026-74869

StoatChat before version 0.15.0 has a missing-authorization flaw in the Subscribe message handler: authenticated users can send a Subscribe message with any arbitrary server ID and receive live UserUpdate events (display names, avatars, status) for members of private servers they are not part of....

EUVD-2026-60088

stoatchat before 0.15.0 contains a missing authorization vulnerability in the Subscribe message handler that allows authenticated attackers to enumerate members and monitor profile updates of private servers without membership. Attackers can subscribe to any server's member-update topic by sendin...

openssl: FFC-DH Peer Validation Uses Attacker-Supplied q

A flaw was found in OpenSSL. A malicious peer can exploit this vulnerability by presenting a specially crafted DHX X9.42 peer key. Due to improper validation of the peer key's subgroup membership, an attacker can recover the victim's private key after a small number of key exchange attempts. This...

BIT-MASTODON-2026-72916 Mastodon: SSRF Protection Bypass via IPv4-compatible IPv6 Addresses

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.4.21, 4.5.14, 4.6.4, and 4.7.0, PrivateAddressCheck.privateaddress? in app/lib/privateaddresscheck.rb normalized IPv4-mapped IPv6 addresses but did not recognize IPv4-compatible IPv6 addresses with...

BIT-DISCOURSE-2026-72726 Discourse: Unauthorized eavesdropping on private AI bot conversations.

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, an authenticated user could eavesdrop on private AI bot conversations through the AI bot reply stream. The issue is fixed in 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0...

BIT-DISCOURSE-2026-72724 Discourse: Private Chat Threat Message Disclosure via Chat Onebox Channel/Threat ID Mismatch

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, plugins/chat/lib/chat/oneboxhandler.rb resolves Chat::Thread by route threadid independently of the route channelid before checking whether the user can preview the selected chat channel. An...