Malicious PDF — malware analysis report

Static analysis result for SHA-256 337b65efdcd2b984…

MALICIOUS

PDF

12.0 KB
MD5: 576baf4769350073d433e3c13a4ccc33 SHA-1: 3fa0e560862799fe7ce1d2d0d18e829a5c0d8b8d SHA-256: 337b65efdcd2b984602c6f195a1b32ffec935ffc79b944a3e0ba8084822865a8
216 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript, indicated by multiple heuristic firings including 'PDF_JAVASCRIPT' and 'PDF_JS'. The critical 'CVE_2007_5659' firing points to the exploitation of a known vulnerability using the 'collab.collectEmailInfo' method to execute a hex-encoded JavaScript stager. This stager, recovered as 'annotation_subject_callee_hex_stage_000.js', is responsible for the malicious behavior. The presence of ClamAV detection further confirms its malicious nature.

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-36165 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36165
  • Annotation subject callee-key hex JavaScript stager high PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER
    PDF JavaScript uses syncAnnotScan()/getAnnots() to read an indirect annotation /Subject stream, percent-decodes it through marker replacement, then uses a callee.toString()-derived key to decode and eval the final exploit stage.
  • 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.
  • 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_obj0007_000.js
3f254d15363cfc46f758dc79a2cb1074c4072b68aa3f4c80a9bf6696d85176e0
pdf-javascript-stream PDF /JS object 7 at offset 0x1A6 1045 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
annotation_subject_callee_hex_stage_000.js
9ef09abee86e84be96886a86553e40934b174cc546c328cfd450bba9c690a71f
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14F 5208 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).