Malicious PDF — malware analysis report

Static analysis result for SHA-256 a992f988c434d896…

MALICIOUS

PDF

136.8 KB Created: 2011-09-08 05:03:17 Authoring application: FPDF 1.6
MD5: 9c250a4e998306788a3e7f335c977091 SHA-1: 82c83c233de7570c0f4ce18576041460384d12e8 SHA-256: a992f988c434d896b48d6db70a3cbf9f365447e43476a85492837aca477b11cb
108 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1566.002 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Exploit.Agent-36874, and a machine learning classifier assigned a high probability of maliciousness. The presence of an XFA form and an AcroForm button with an action trigger suggests an attempt to exploit PDF vulnerabilities. The ML classifier's high confidence score and the ClamAV detection strongly indicate this PDF is designed to deliver a malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 4

  • ClamAV: Pdf.Exploit.Agent-36874 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-36874
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • AcroForm button with action trigger low PDF_ACROFORM_BUTTON
    PDF contains a /Btn form field together with a SubmitForm/URI/Launch/JS trigger — this is the building block of fake 'Download' or 'Open' button overlays used in PDF phishing lures
  • 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_001_off000008ed.bin
83ba8a6efdb5ccf1d3202f3b96f15f9a3f7551ab9d9e77b310750e875e32cac4
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x8ED 1436 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).