Malicious PDF — malware analysis report

Static analysis result for SHA-256 812331d11b9e93c4…

MALICIOUS

PDF

3.6 KB Created: 2008-07-26 19:43:58 Authoring application: Scribus 1.3.3.12 (via Scribus PDF Library 1.3.3.12)
MD5: 72df927a688c27fa249c9191a59b4e36 SHA-1: b2533f2765dff02d179a62281a4d62102b0b2c9c SHA-256: 812331d11b9e93c4bdeec5b21f68b1375ca3c5dccd6edc19b254ae38c3ba996d
296 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link

The sample is a PDF file that contains embedded JavaScript. Heuristics indicate the use of eval() and String.fromCharCode, along with a critical detection for CVE-2007-5659 (Collab.collectEmailInfo). This suggests the JavaScript is designed to exploit a vulnerability in Adobe Reader, likely to download and execute a second-stage payload. The presence of deobfuscated JavaScript artifacts further supports this analysis.

Heuristics 8

  • 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-35551 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35551
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • Suspicious extracted artifact high 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.
  • String.fromCharCode medium PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically (matched inside decoded stream)
  • 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.

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0013_000.js
efabb50dce0b55fc84930a6ba7a10c04611b48e52f2f145ec6e9763e3e311b79
pdf-javascript-stream PDF /JS object 13 at offset 0x3CE 3779 bytes
Detection
ClamAV: Pdf.Exploit.Agent-35551
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
acroform_b64_00.js
b2ef249bba64ae8cd359e8cce7f840bcbf4a4d7eb3847b55cdac50d292a1b0fd
deobfuscated-js PDF AcroForm base64 (decompressed) at offset 0x772 2173 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).