CVE-2026-19867
Mattermost versions 11.10.x <= 11.10.0, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10 fail to cap the number and size of mention key
CVSS
4.3
Medium
EPSS
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KEV
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Exploit Today
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0-100
Published: Oct 16, 2026 · Last modified: Oct 16, 2026 · CWE-770
Not enough EPSS history yet.
Mattermost versions 11.10.x <= 11.10.0, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10 fail to cap the number and size of mention keys stored in a user's notification properties, and to bound the quadratic multibyte-keyword matching performed for each post, which allows an authenticated user to degrade post-processing latency and consume excessive CPU on behalf of other members of any channel they share via storing an oversized notify_props.mention_keys list on their own profile.. Mattermost Advisory ID: MMSA-2026-00773
CVECVSSEPSSKEVRExploitTitleMod.
CVE-2026-1113846.5 MED—
———Nezha 1.0.0 before 2.3.15 contains a memory exhaustion vulnerability in the dashboard file manager WebSocket endpoint because fmStream never calls SetReadLimit, leaving message size unbounded. Authenticated users with file manager scopes can send one oversized binary message to /api/v1/ws/file/:id, triggering an OOM kill that drops all agent monitoring.6hCVE-2026-1113836.5 MED—
———Nezha from 2.0.13 before 2.3.15 contains a resource exhaustion vulnerability that allows authenticated users to open unbounded concurrent connections to the /api/v1/ws/transfer WebSocket endpoint. Attackers can hold thousands of subscriptions created by ServerTransferClass.Subscribe without limits, exhausting file descriptors, memory, and goroutines and blocking agent gRPC reconnections.6hCVE-2026-1094687.5 HIG—
———Allocation of resources without limits or throttling in ASP.NET Core allows an unauthorized attacker to deny service over a network.6hCVE-2026-1099325.9 MED—
——0undici is an HTTP client library for Node.js. In versions 5.15.0 through 6.29.0, 7.0.0 through 7.30.0, and 8.0.0 through 8.12.1, its WebSocket client, including the bundled WebSocket exposed by Node.js, can be driven to exhaust process memory by a malicious or compromised WebSocket server. For every PING frame received, the client automatically writes a PONG response and ignores the backpressure signal from the socket write, so a server that streams small PING frames while never reading the client's PONGs makes the outbound write queue and heap grow without bound until the Node.js process runs out of memory and terminates. The attack is remote and unauthenticated, needs only a normal WebSocket connection, and is asymmetric, since small inbound PINGs produce a much larger retained outbound queue, with availability the only impact. The issue is fixed in undici 6.29.1, 7.30.1, and 8.12.2, which pause WebSocket frame parsing when the automatic PONG response hits socket backpressure and resume on drain, bounding the outbound queue, and users should upgrade to one of those versions or later. There is no workaround.13hCVE-2026-1099245.9 MED—
——0undici is an HTTP client library for Node.js. In versions 6.5.0 through 6.29.0, 7.0.0 through 7.30.0, and 8.0.0 through 8.12.1, its EventSource client can be driven to exhaust process memory by a malicious or compromised Server-Sent Events peer. By sending millions of tiny completed data fields with no blank event separator, or a single unfinished line split across many chunks, the parser retains a growing amount of per-field and per-chunk state that the byte-based maxEventSize and maxResponseSize limits do not bound, and because maxResponseSize is enforced on the compressed body before decompression, a small compressed response can expand into enough retained memory to terminate the process. An application only needs to maintain an EventSource connection to an untrusted peer, which controls only the response, and availability is the only impact. The issue is fixed in undici 6.29.1, 7.30.1, and 8.12.2, which bound the retained parser state independently of the byte limits, and users should upgrade to one of those versions or later. There is no workaround.13hCVE-2026-1048277.5 HIG—
——0react/http is an event-driven, streaming HTTP client and server implementation for ReactPHP. From 1.0.0 until 1.11.1, React\Http\Browser uses ClientRequestStream::handleData() to append response-header bytes to an internal buffer without enforcing a size limit. A remote server can send a valid status line and partial header, withhold the \r\n\r\n or \n\n header terminator, and continue streaming data so the buffer grows for the life of the connection. Applications that fetch attacker-controlled or attacker-influenced URLs, including URLs reached through redirects, can exhaust PHP memory_limit and crash the event-loop or worker process. Confidentiality and integrity are unaffected. This issue is fixed in version 1.11.1.14h