Malicious PDF / .TXT — malware analysis report

Static analysis result for SHA-256 dcb9ccbd51d43e71…

MALICIOUS

PDF / .TXT

2.0 KB
MD5: ef288d124d62f46c67be52d4e9be0448 SHA-1: 26d590dff236a781733e0d1d74853b1e20a2b392 SHA-256: dcb9ccbd51d43e7175f88b22c18202ac17dc1611315a06b7d17fb133d7fcccd9
218 Risk Score

Malware Insights

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

The PDF file contains embedded JavaScript that utilizes `eval()` and `unescape()` functions, indicating obfuscation. Critical heuristics identify the use of `Collab.collectEmailInfo` (CVE-2007-5659) and a ClamAV detection signature (Pdf.Exploit.Agent-35930). The embedded JavaScript is likely responsible for downloading and executing a secondary payload, a common technique for exploiting PDF vulnerabilities.

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 0x6D8 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
41b3d520e87420c1fbb390583f12b252a9776618e7a7f983b3938a257db4ea05
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x189 2640 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 3 eval/decoder/string-building token(s).