Malicious PDF — malware analysis report

Static analysis result for SHA-256 867b826f80177e30…

MALICIOUS

PDF

118.7 KB
MD5: 5f37dcd6e222818ae52cef1b23a35784 SHA-1: f029cec256f992e7a067adddfc9daf790dcb5823 SHA-256: 867b826f80177e30f2a8d08e938a39ab1eee9d3a4c6ae14ffb1614d3a4e85a42
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 JavaScript

The PDF contains embedded JavaScript, including a large comment-padded eval stager, indicating an attempt to obfuscate malicious code execution. The 'eval()' and 'String.fromCharCode()' calls within the JavaScript stream strongly suggest the execution of arbitrary code. ClamAV detection as 'Pdf.Exploit.Agent-36086' further confirms its malicious nature. The primary attack pattern involves leveraging JavaScript to download and execute a secondary payload.

Heuristics 7

  • ClamAV: Pdf.Exploit.Agent-36086 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36086
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • Large comment-padded JavaScript eval stager high PDF_JS_LARGE_COMMENT_PADDED_EVAL
    PDF JavaScript contains a very large stream padded with long random-looking block comments around String.fromCharCode and eval. This is an exploit-kit obfuscation shape used to bury a decoder and recovered stage inside noise, not normal PDF form automation.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
ea747328f017edc366d0d5be1d582a51c6fbdf6a2086129f15b2594747740662
pdf-javascript-stream PDF /JS object 6 at offset 0x143 627252 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 42 long base64-like blob(s).