Malicious PDF — malware analysis report

Static analysis result for SHA-256 81d8a7e062a9496f…

MALICIOUS

PDF

9.2 KB
MD5: 2ac6e647602bcba7fa320bbb5db30897 SHA-1: acf709e9fee9b20c8dc8183af5d845a02e94029b SHA-256: 81d8a7e062a9496f5d72ef1bfde4bcce382a0c37fc360a5c0251ea65ba918ccf
180 Risk Score

Malware Insights

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

The file is a PDF containing embedded JavaScript that leverages the CVE-2007-5659 vulnerability (Collab.collectEmailInfo). The JavaScript is heavily obfuscated but appears to be designed to download and execute a secondary payload. The presence of multiple deobfuscated JavaScript files suggests a multi-stage attack. The ClamAV detection further confirms its malicious nature.

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
ec2e34beb3415f9f22babaa5318729d0ccd1f5924b359e4b299512ccb70791e1
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 12169 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
0a900881ec14c4f526ef937096a058e0966890eda8d69280280e177f1b885a8c
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 5037 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).