Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7d7e5ba580707ff…

MALICIOUS

PDF

15.7 KB
MD5: 5d4847f708f8fd63930c7e37fcc54dde SHA-1: 7e8d7d90b3ba302ab2a61a3d17418d4797a0b997 SHA-256: e7d7e5ba580707ff2b759cd96eadab52f289ffc461ca660093eb0bd8818de99d
166 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF contains embedded JavaScript, indicated by multiple heuristic firings including 'PDF_JAVASCRIPT', 'PDF_JS', and 'PDF_EVAL'. The 'PDF_JS_LARGE_COMMENT_PADDED_EVAL' heuristic specifically points to a stager pattern. ClamAV detection as 'Pdf.Exploit.Agent-36086' further confirms its malicious nature. The primary attack vector appears to be exploiting PDF vulnerabilities to run obfuscated JavaScript, which is designed to download and execute further malicious content.

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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0006_000.js
81a6fa145409dda601c49a581ddfd52f70a9e6350dbca1ddcbf8f6867ce6473d
pdf-javascript-stream PDF /JS object 6 at offset 0x143 425148 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).
stream_001_off00003b64.bin
959ccdb766c8ddb156306390b5ef47dc5225b4593c10b94bff8caf3f750e1a18
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x3B64 300 bytes