Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5ab0e3e0994f69d…

MALICIOUS

PDF

12.2 KB
MD5: 33a9423ad1a34fda932571a8dbf316da SHA-1: 86bb344f15e63bb3f0cb51200b71130a09f2b442 SHA-256: a5ab0e3e0994f69d95614849b5a94733615b60ecb1c9697b3cb2b73098f6668e
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 exploitation of a known vulnerability using the 'Collab.collectEmailInfo' method to execute JavaScript. This JavaScript is likely designed to download and execute a second-stage payload, as suggested by the presence of deobfuscated JavaScript files ('legacy_pdfkit_stage_000.js', 'legacy_pdfkit_stage_001.js') which are often used in multi-stage attacks. 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
3308fce00fa26a1f35cae2a863a0aee7d3a013062683db2eb8974d2172a32ace
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x315 12480 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
3e62073f7d5039f8b07bf5855f8cfc5387a4b32dbc7bc850399fda84518519c9
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x315 5157 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).