Malicious PDF — malware analysis report

Static analysis result for SHA-256 5506935919c19d3a…

MALICIOUS

PDF

11.5 KB
MD5: c57a4e2168485781136da4416f5b3186 SHA-1: 1971471b9d0ce00e3337772146e1fbefb78a7e32 SHA-256: 5506935919c19d3a4dcf5a54405bf05bedc2f18f6e256e1ad69bc04065d5747c
146 Risk Score

Malware Insights

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

The sample is a PDF file that leverages the CVE-2007-5659 vulnerability through embedded JavaScript. The JavaScript is heavily obfuscated but appears to be designed to download and execute a second-stage payload. The presence of multiple obfuscated JavaScript streams and the critical ClamAV detection for Pdf.Exploit.Agent-36079 strongly indicate malicious intent.

Heuristics 6

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-36079 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36079
  • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
ef8bdac794684ae9cd4eb7091d80e1c5ca478c06c639d72d01626c1f7ce78b6d
pdf-javascript-stream PDF /JS object 7 at offset 0x19C 578 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
522e2a3f0a5afa83a832ef3b77549ebedd5476e43ea31cd4c04a43d97614970a
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 11802 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
88df62064eeb9a0f924ff124ec0a2230e4087ddac1521b289eef758d2894d86b
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x36F 4829 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).