ET HUNTING GoogleSheets API V4 Activity (Possible Exfil)

alert http $HOME_NET any -> $EXTERNAL_NET any (
    msg:"ET HUNTING GoogleSheets API V4 Activity (Possible Exfil)";
    flow:established,to_server;
    http.method;
    content:"PUT";
    http.uri;
    content:"/v4/spreadsheets/"; startswith;
    content:"/values/"; distance:0;
    content:"!"; distance:0;
    content:"valueInputOption|3d|USER_ENTERED"; distance:0; fast_pattern;
    http.host; bsize:21;
    content:"sheets.googleapis.com";
    http.request_body;
    content:"|5b 22|";
    pcre:"/^[a-f0-9]{8}-([a-f0-9]{4}-){3}[a-f0-9]{12}\x22\x2c/RP";
    content:"|22|20";
    pcre:"/(?:2[4-9]-[0-9]{2}-[0-9]{2})\s(?:([0-9]{2}:){2}[0-9]{2})\x22/RP";
    classtype:bad-unknown;
    sid:2063452; rev:1;
    metadata:attack_target Client_Endpoint, tls_state TLSDecrypt, created_at 2024_08_19, deployment Perimeter, deployment SSLDecrypt, confidence Medium, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2025_07_14, former_sid 2857976;
)