Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6a176dffe025620…

MALICIOUS

PDF

9.6 KB
MD5: 8881e59815a073d2aaa56b16e575dbdb SHA-1: a662708e2fb72d6a059b0b4bf9b5e3b3d60879a4 SHA-256: b6a176dffe025620b902568d1ff529b73e5782b39bd32a5fe7b0a3a2253d98df
178 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.001 Malicious Link T1204.002 Malicious File

The file is a PDF containing embedded JavaScript, which is a common technique for exploiting vulnerabilities in PDF readers. The critical heuristic 'CVE_2007_5659' indicates the use of a known exploit targeting this vulnerability. The embedded JavaScript streams, particularly 'legacy_pdfkit_stage_000.js', are likely responsible for downloading and executing a secondary payload, as suggested by the file's malicious verdict and the nature of the extracted artifacts. 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
31e33bc70426eded998ab7c37fd4c279f3f471e1e63ebc414de2b2d1f2f7e120
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 12373 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
92499a77987c2da0faffd5431463674bb171811d470cd96d1c6bf0663411ed1c
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 5204 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).