たぬきのかくちょう

AI Security Review

Evidence context: threat category none; evidence quality moderate.

This extension, "たぬきのかくちょう" (Tanuki's Memo), shows 22 total findings but none indicate actual malicious behavior. The 19 high-severity findings in the malware-signature category are all code-smell rules that fire on standard library code, not malware signatures. Specifically, YARA--postinstall_obfuscation, YARA--postinstall_file_manipulation, YARA--postinstall_network_communication, YARA--postinstall_system_command, and YARA--postinstall_crypto_operations all match in /tmp/extract-18fb4480d85df9acb209ec4ece5bd2516aaa904cde85d15d4611ba3038f63296-1555076887/js/jquery.js and css/jquery-ui.css. Per CVEQ's known false-positive patterns, postinstall_* rules match basic Node.js patterns (fetch, exec, fs, crypto, process.env) and are classified as code-smell/low severity noise, not malware.

The 3 network findings (NET-JQUERY_AJAX-js/jquery-ui.js-3080, NET-JQUERY_AJAX-js/jquery-ui.js-15883, NET-JQUERY_AJAX-js/jquery-ui.js-15887) are legitimate jQuery AJAX calls in the bundled jQuery UI library, not suspicious network activity to unknown domains. The findings_summary confirms 0 actual malware-signature findings and 19 code-smell findings, despite the display showing high severity.

The extension targets a Japanese community site (Zantan Tanuki) with only 23 users and an anonymous developer ([email protected]). While the developer is not verified and the user count is low, the code itself contains no evidence of credential theft, browser hijacking, proxyware, or data exfiltration. The extension description states it improves readability and usability for the site, which is consistent with the presence of jQuery libraries for DOM manipulation.

Counterargument: A skeptic might argue the anonymous developer and low user count warrant concern, especially with 19 high-severity findings. However, the severity labels are misleading—these are code-smell findings on bundled jQuery code, not actual malware. The findings_summary explicitly shows "malware-signature":"0" and "code-smell":"19", confirming the nature of these detections. Without actual malware signatures, suspicious IoCs, obfuscation in non-locale files, or behavioral evidence of harm, the extension does not meet the threshold for confirmed_malicious or confirmed_risk. The findings are entirely explained by known false-positive patterns in CVEQ's detection system.

Key Reasons

• All malware-signature findings are postinstall_* code-smell rules matching bundled jQuery library code
• Network findings are legitimate jQuery AJAX calls, not suspicious domains
• findings_summary shows 0 actual malware-signature findings, 19 code-smell findings
• No obfuscation, IoCs, or behavioral evidence of malicious activity
• Extension purpose (readability enhancement) matches jQuery library presence

False Positive Considerations

• postinstall_* YARA rules matching Node.js patterns in bundled jQuery
• Code-smell rules (SQLInjection, NoUseWeakRandom) on standard library code
• Bundled dependency files triggering multiplicative false positives
• Severity inflation on code-smell findings

Reviewed 2026-04-30; recommended action: suppress false positive; model confidence 85%.