Malicious PDF — malware analysis report

Static analysis result for SHA-256 19777f5de2df9331…

MALICIOUS

PDF

136.8 KB Created: 2011-09-08 05:03:17 Authoring application: FPDF 1.6
MD5: a83b8e6407e3871a2dfe7b34f94166a9 SHA-1: 08da5aed1431e199f1e112814e5c22228a1c1869 SHA-256: 19777f5de2df933117911b0ab29e0791ed7c4f2007a4e93180c9b9ae9750c129
110 Risk Score

Malware Insights

MITRE ATT&CK
T1203 Exploitation for Client Execution T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically identifying it as Pdf.Exploit.Agent-36874. It utilizes XFA forms and AcroForm buttons, indicating an exploit is likely present to execute code. The presence of a long encoded blob within an extracted stream further supports the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://www.xfa.org/schema/xfa-data/1.0/
    • http://ns.adobe.com/xfdf/
    • http://www.xfa.org/schema/xfa-form/2.8/

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_001_off000008ed.bin
9553986b72081aa10be66474a68a06529d605c3e665bf4802189f4b755ed1b6c
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x8ED 1455 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).