Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to properly validate msgpack-encoded WebSocket frames before memory allocation which allows an unauthenticated remote attacker to crash the server process and cause a full service outage for all users via a crafted binary WebSocket message sent to the public WebSocket endpoint.. Mattermost Advisory ID: MMSA-2026-00647

A stack-based buffer overflow via UCS-2 type confusion in convert_charset() in Netatalk 2.0.4 through 4.4.2 allows a remote authenticated attacker to execute arbitrary code or cause a denial of service.

An improper link resolution vulnerability in Netatalk 3.0.2 through 4.4.2 allows a remote authenticated attacker to read arbitrary files or overwrite arbitrary files via attacker-controlled symlink creation.

Netatalk 2.0.0 through 4.4.2 generates AFP session tokens derived from predictable process IDs, which allows a remote authenticated attacker to cause a denial of service by exploiting the reconnect mechanism.

A time-of-check time-of-use (TOCTOU) condition in the ad_flush function in Netatalk 3.0.0 through 4.4.2 involves root-privileged file operations, which may allow a remote attacker to cause limited data modification under specific race conditions.

An out-of-bounds read in ASP session ID handling in Netatalk 1.3 through 4.4.2 allows an adjacent network attacker to obtain limited information or cause a denial of service via a crafted ASP request.

An off-by-two error in lp_write() in papd in Netatalk 2.0.0 through 4.4.2 allows an adjacent network attacker to modify limited data or cause a minor service disruption via crafted print data.

An integer underflow in dsi_writeinit() in Netatalk 1.5.0 through 4.4.2 allows a remote unauthenticated attacker to cause a denial of service via a crafted DSI write request.

Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to check integration URL for path traversal which allows an malicious authenticated user to call an arbitrary API via system admin Mattermost auth token using via path traversal in integration action URL.. Mattermost Advisory ID: MMSA-2026-00640

A heap-based buffer overflow in the CNID daemon comm_rcv() function in Netatalk 2.0.0 through 4.4.2 allows a remote authenticated attacker to execute arbitrary code with escalated privileges or cause a denial of service.