Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8d1183853b1979e…

MALICIOUS

PDF

9.3 KB
MD5: 57a8d1413bf7880cc98fb9c80ef74ed3 SHA-1: a1379c3a6ee3d43b9fcd816ef9d913a63a5faaf4 SHA-256: f8d1183853b1979e4b6822cfe45614f2676a131751bb596fd6ce0d096e840646
178 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 (Pdf.Exploit.Agent-35905). Heuristics indicate the use of CVE-2007-5659, specifically targeting the Collab.collectEmailInfo method to execute JavaScript. This JavaScript is further obfuscated and likely downloads and executes a second-stage payload.

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-35905 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35905
  • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
d8a6b4ad1abf04d0c4a4f89535cfb57f7312edef25c443f4e844c8ec9d0929dd
pdf-javascript-stream PDF /JS object 7 at offset 0x19B 352 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
72e0ee65599ba907b0f0df96038c7e44054cc182be60b3c9907d827355b24866
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 12040 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
4e3790ea234f900385e7bf287ccc40050a7a6a46b25656f149bce1fd82ba53ee
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 5001 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).