CVE-2026-11820

Mattermost Plugins versions <=11.6 10.18.11 11.3.6 11.6.5.0 fail to sanitize error responses from the OpenAI API before logging, which allows a user with access to server logs or support packets to obtain a valid or partially reconstructable OpenAI API key via inspection of mattermost.log entries generated during authentication failures. Mattermost Advisory ID: MMSA-2026-00609

HCL Traveler for Microsoft Outlook (HTMO) is susceptible to a sensitive data exposure vulnerability which could allow an attacker to exploit application information to then attempt additional attacks and cause unknown behavior in the application.

vLLM is an inference and serving engine for large language models (LLMs). From 0.8.3 to before 0.14.1, when an invalid image is sent to vLLM's multimodal endpoint, PIL throws an error. vLLM returns this error to the client, leaking a heap address. With this leak, we reduce ASLR from 4 billion guesses to ~8 guesses. This vulnerability can be chained a heap overflow with JPEG2000 decoder in OpenCV/FFmpeg to achieve remote code execution. This vulnerability is fixed in 0.14.1.

vLLM is an inference and serving engine for large language models (LLMs). Prior to 0.23.1rc0, the fix for CVE-2026-22778, which introduced a sanitize_message helper that strips object-repr memory addresses from error messages before they reach the client, is incomplete: several response paths echo str(exc) directly to clients without calling sanitize_message. The unsanitized sites include the Anthropic API router in vllm/entrypoints/anthropic/api_router.py (the POST /v1/messages and POST /v1/messages/count_tokens handlers), the Server-Sent Events streaming converter in vllm/entrypoints/anthropic/serving.py, and the realtime speech-to-text WebSocket in vllm/entrypoints/speech_to_text/realtime/connection.py. These paths catch the exception inside the route coroutine and construct the JSONResponse themselves, bypassing the sanitizing global FastAPI exception handler, and WebSocket frames do not traverse that handler chain at all. Using the same primitive as the parent issue, an unauthenticated attacker can send malformed image bytes through the Anthropic Messages API image content parts so that PIL.Image.open raises an UnidentifiedImageError whose message contains the BytesIO object repr, leaking the heap memory address verbatim in the error.message field of the response body. This vulnerability is fixed in 0.23.1rc0.

GitLab has remediated an issue in GitLab EE affecting all versions from 19.1 before 19.1.1 that under certain conditions could have allowed a user to access sensitive information that had already been committed to a project, due to insufficient output filtering in Duo Workflows.

A flaw was found in foreman-mcp-server. This component utilizes two distinct logging mechanisms that can expose sensitive session and authentication data. One mechanism logs session identifiers, which are treated as authentication credentials, at an informational level. The other, when debug logging is enabled, incompletely sanitizes HTTP request headers, leading to the cleartext logging of sensitive information such as authorization tokens and API keys. This vulnerability can result in a confidentiality breach, as sensitive authentication data is persisted in plain text within container logs, increasing the risk if logs are forwarded to a centralized platform.