Malicious PDF — malware analysis report

Static analysis result for SHA-256 a61e0879127e5045…

MALICIOUS

PDF

136.8 KB Created: 2011-09-08 05:03:17 Authoring application: FPDF 1.6
MD5: 1db1f670018271db649a057c66e5fa0e SHA-1: 0da9ef5006b2da06c079ba9c3deda4758879ee22 SHA-256: a61e0879127e50450b6c43a974e18aa8f7d156df28da14b58f39ab383ebc225b
108 Risk Score

Malware Insights

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

The file is identified as malicious by ML classification and ClamAV, specifically as Pdf.Exploit.Agent-36874. The presence of XFA forms and AcroForm buttons with action triggers suggests an exploit is embedded within the PDF structure. The ML classifier's high confidence score further supports this. While no scripts were directly extracted, the nature of the exploit and the 'Suspicious extracted artifact' heuristic indicate it likely attempts to download and execute a secondary 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
322727de14a36934897c601f54451243f0806369208fc696122ac7ebe42dbb80
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x8ED 1425 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).