Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f222c44ef40abdb…

MALICIOUS

PDF

11.8 KB
MD5: c0ef41f170aaedc1cbaf441646ea9174 SHA-1: ad48963ed527031eccf8d807c501cf531d586e08 SHA-256: 1f222c44ef40abdba7b297937da25a84f190c398b1604f3845e59ca0d9dc42b6
146 Risk Score

Malware Insights

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

The file is a PDF containing embedded JavaScript, identified as malicious by ClamAV. The critical heuristic CVE_2007_5659 indicates the use of a known exploit targeting Adobe Reader, specifically leveraging the Collab.collectEmailInfo function. The embedded JavaScript streams, named legacy_pdfkit_stage_000.js and legacy_pdfkit_stage_001.js, are likely responsible for downloading and executing a secondary payload. The presence of these stages suggests a multi-stage attack designed to compromise the user's system.

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-35903 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35903
  • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
860eae5f96eb426380281c575a089242b50523bbb4bbb8dd765e582cd9c07d2e
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 294 bytes
legacy_pdfkit_stage_000.js
49e0e006640605691c40265d585086fa31df6b7d72c2794c06eb895f5e86b17a
deobfuscated-js z-percent hex-pair decoded JavaScript at offset 0x2E8 5008 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
ccd6859a4cf4827a41b92d0a189d980e47a2781ba3cf9ee4e3408a7949cb8f16
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2E8 12123 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).