Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbd8fbc5b3142760…

MALICIOUS

PDF

9.3 KB
MD5: 3f80af499fa676caf81245d590332d8b SHA-1: 9619389276bf89836c448887b70a7503af1d5e61 SHA-256: dbd8fbc5b314276053e732d99d9635e4299fb24ec6f6846125c2f92675b4860c
178 Risk Score

Malware Insights

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

The file is a PDF containing embedded JavaScript, which is a common delivery mechanism for exploits. The critical heuristic CVE_2007_5659 indicates the use of a known vulnerability (Collab.collectEmailInfo) to launch JavaScript. The embedded JavaScript streams, particularly 'legacy_pdfkit_stage_000.js', are heavily obfuscated but suggest the execution of further malicious code. 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
deb78fbb7836ac1ace96bc58a1d6999f290eec32ef7fb5804cc00dc8d9bcf72f
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 11925 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
5b078028b5d48bf084251e003de173389885ecc3837186e0a2446444b07548c2
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 4986 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).