Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b21100b828b7775…

MALICIOUS

PDF

788.0 KB First seen: 2026-05-04
MD5: 3668b018b4bb080d1875aee346e3650a SHA-1: fc53525f4e2e5b8ebe86778c20fd8916612cfd29 SHA-256: 5b21100b828b77758bfd6495c924e71f8bbd890c78d07067928bd7beccae087e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating it is a dropper. The presence of JavaScript within an XFA form, combined with encryption and an OpenAction, suggests the script is used to obfuscate and deliver a secondary payload. The embedded JavaScript stream is the primary mechanism for executing the malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Dropper.Agent-7263545-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-7263545-0
  • Encrypted PDF carries /OpenAction — payload hidden from static analysis high PDF_ENCRYPTED_WITH_JS
    PDF declares /Encrypt and also references an executable trigger (/OpenAction). Document encryption hides the JavaScript body and stream contents from static scanners — combined with auto-execution indicators this is a known evasion pattern used to deliver weaponised JavaScript that the analyst cannot inspect without the decryption key.
  • JavaScript action low 1 related finding 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.
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • 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://ns.adobe.com/xdp/ In PDF document text
    • http://www.xfa.org/schema/xci/3.0/In PDF document text
    • http://www.xfa.org/schema/xfa-template/2.8/In PDF document text
    • http://www.xfa.org/schema/xfa-data/1.0/In PDF document text

Related samples 8

Ranked by shared artifacts, heuristics, extracted URLs, CVEs, and signatures.

Full JSON: related samples API

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_000_off0006d7f3.js decompressed-pdf-stream PDF FlateDecoded stream at offset 0x6D7F3 289498 bytes
SHA-256: dcefc16710d335e69f60cdd8a0e174d43939d02eaa8dd4c6d7ce4ca63f06495b

Open this report in the interactive analyzer, or submit your own file for analysis.