{"id":"AZL-107021","summary":"CVE-2026-78659 affecting package azl-otel-collector 0.127.0-1","details":"When \"Trailer\" headers are sent by a client, the HTTP server internally uses the header values to populate the Request.Trailer map passed to the server handler. Because Request.Trailer is a map, each entry incurs memory overhead. For HTTP/2 servers, a malicious client can exploit this by sending a \"Trailer\" header that declares a large number of fields, causing the server to allocate a disproportionate amount of memory while bypassing Server.MaxHeaderValueCount and Server.MaxHeaderBytes limits. This exploit is not applicable for HTTP/1 servers, which do not support multiplexing a large number of requests over one TCP connection, and whose Server.MaxHeaderBytes are calculated differently.","modified":"2026-10-12T05:33:09Z","published":"2026-10-08T23:17:03Z","upstream":["CVE-2026-78659"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-78659"}],"affected":[{"package":{"name":"azl-otel-collector","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/azl-otel-collector"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"0.127.0-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-107021.json"}}],"schema_version":"1.9.0"}