Detection Templates Released for vLLM Multimodal Info Leak CVE-2026-22778

New detection content has been published for CVE-2026-22778, an information disclosure flaw in vLLM multimodal OpenAI-compatible servers that can expose a Python BytesIO heap address in error messages. The bug is triggered when a malformed image is submitted to a multimodal endpoint, causing Pillow-related exceptions such as UnidentifiedImageError to return internal object representations containing 0x-style memory addresses. The leak affects vulnerable versions through vLLM 0.14.0 and was sanitized in vLLM 0.14.1, where the sanitize_message handling prevents the address disclosure.

Rapid7 added a Metasploit auxiliary scanner to identify exposed servers by reading the /version banner, enumerating models via /v1/models, and sending a single benign malformed image request to test for the leak without reaching the reported JPEG2000 heap-overflow path. ProjectDiscovery also published a Nuclei template for the same issue, targeting endpoints such as POST /v1/chat/completions and checking for the characteristic HTTP 400 response and leaked heap-address patterns. The flaw is significant because the disclosed address can help defeat ASLR as an early stage in a potential remote code execution chain.