Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb113e2711791ea8…

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: 49be8864535f05ff87ac2ff13990b279 SHA-1: 2ac29cf9d546c998f9b79322d7a98034016ab277 SHA-256: bb113e2711791ea8a5d53a48485a43efee78c5856617507e65509595dfabe71e
296 Risk Score

Malware Insights

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

The file is a PDF document that contains embedded JavaScript. Heuristics indicate the use of eval() and String.fromCharCode, along with a critical finding for CVE-2007-5659 (Collab.collectEmailInfo), suggesting an exploit targeting Adobe Reader. The embedded JavaScript, particularly the deobfuscated acroform_b64_00.js, likely decodes and executes a second-stage payload. ClamAV also detected this file as Pdf.Exploit.Agent-35551.

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
04ec51ff021b89f87c77619cdb82bbaf6e628916629c4e2b1d97733bd85cc9f7
pdf-javascript-stream PDF /JS object 13 at offset 0x3CE 3883 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
8727eeb2b629e24c6a7a99655f943b89f98978ed0b65275a19274158c0aec756
deobfuscated-js PDF AcroForm base64 (decompressed) at offset 0x772 2251 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).