Malicious PDF — malware analysis report

Static analysis result for SHA-256 857f851347d75a98…

MALICIOUS

PDF

11.9 KB
MD5: 14c96e9ef8b8d477af15cfe716faf844 SHA-1: aab60a9cc579f0aec36f7f11c37083b95193ca9f SHA-256: 857f851347d75a98b1f14aa810fe49bd6941e85e5b60b2f0562565116543c40b
138 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' heuristic specifically points to the use of 'Collab.collectEmailInfo' for executing JavaScript, a known technique for exploiting PDF vulnerabilities. The presence of deobfuscated JavaScript files ('legacy_pdfkit_stage_000.js', 'legacy_pdfkit_stage_001.js') suggests the script's purpose is to download and execute further malicious content. The ClamAV detection further confirms its malicious nature.

Heuristics 5

  • 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-36065 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36065
  • 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.
  • 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
9c67560e8c63b720885d3efc1627b844b86a6ec08e99e5b65a22eae832045756
pdf-javascript-stream PDF /JS object 7 at offset 0x19C 431 bytes
legacy_pdfkit_stage_000.js
c47830644673c5766dada019ad0c8b246261fefac3f1bd92d733883ffa3b57be
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x315 12171 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
11a44409dedb9d999bcda29dc6ef1c23ed51dcec26aae31030100c4872b7d7e8
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x315 5016 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).