Malicious PDF — malware analysis report

Static analysis result for SHA-256 a646aa840e21a85d…

MALICIOUS

PDF

2.0 KB
MD5: cd23931cd33e41a37af9eb8c2c943677 SHA-1: b1ac7e7a066e6d3f11b4d1027096cde97233eb0a SHA-256: a646aa840e21a85d070dfaba33b60bc5a5e76c3f9efbc1107b89e0ec8232f781
218 Risk Score

Malware Insights

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

This PDF file contains embedded JavaScript that leverages the CVE-2007-5659 vulnerability (Collab.collectEmailInfo). The JavaScript is obfuscated and uses eval() and unescape() functions, indicating an attempt to hide malicious code. The primary goal appears to be the execution of arbitrary code, likely to download and run a second-stage payload. The presence of multiple obfuscated JavaScript files further supports this assessment.

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-35930 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35930
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution (matched inside decoded stream)
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj111611_000.js
f23e505f155bfa9b9f356fa9fddf8d7fcafcc37fc2df3878e575e72c00c819d4
pdf-javascript-stream PDF /JS object 111611 at offset 0x6D6 697 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
3cd332d21455bbeb125ca56f0051fbbff2aa11558a095dc1dd6df92c2ca34799
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x189 2634 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).