Malicious PDF — malware analysis report

Static analysis result for SHA-256 9bacc15c74ef3e73…

MALICIOUS

PDF

12.2 KB
MD5: 1dd0e0a0f95e1fe6f17cb0700bfcd731 SHA-1: 792b8173c465e83130dd89bc8339a8e02eef4962 SHA-256: 9bacc15c74ef3e73c8850427969a3a5043e7a161d33e07b21ba5ebe3ac5c30d4
186 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that leverages the 'Collab.collectEmailInfo' method to exploit CVE-2007-5659. This exploit is used to decode and execute a hex-encoded JavaScript stager. The stager is responsible for downloading and executing a secondary payload, indicating a multi-stage attack. The ClamAV detection 'Pdf.Exploit.Agent-36063' further confirms the malicious nature of the file.

Heuristics 7

  • 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-36063 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36063
  • 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.
  • 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.
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
eb39e2de4dbbc100de6d3e30aa43ff78fa075618862ba1ebba5151ea3a3b848d
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 273 bytes
annotation_subject_callee_hex_stage_000.js
76f1c337dd85a50268dd01b7a18d9c52c8072110cfed7d2725ba13842cbd109f
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 5205 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
389b7d4ad4e5f5aaeda8cd10468be43b88fbe0ecfc2f552c8c8fd870430ba8a7
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2D6 12340 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
deobfuscated.js
ee77b0ea2e97a84fc8d51d36a6c35c29e71c78c7e666bc90cb25dca3c4efd842
deobfuscated-js PDF JavaScript deobfuscation pass 78487 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).