Malicious PDF / .TXT — malware analysis report

Static analysis result for SHA-256 146d7756c5ac2c35…

MALICIOUS

PDF / .TXT

242.6 KB
MD5: c1762ea639479d85a85918d017c205f2 SHA-1: 78b17eaf625d3364905e404ce44cad03d2ce3f0b SHA-256: 146d7756c5ac2c35197072ca964ae19f487c9647128e370d930f5222503ab02e
136 Risk Score

Malware Insights

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

The PDF file contains JavaScript and utilizes XFA forms, which are known vectors for exploiting PDF vulnerabilities. The ML classifier strongly indicates maliciousness. The embedded URL 'http://www.bitstream.com' is suspicious and likely serves as a download source for a secondary stage. The exploit cluster and JavaScript execution point towards a downloader or dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8569

Heuristics 6

  • PDF JavaScript exploit cluster critical PDF_JS_EXPLOIT_CLUSTER
    PDF combines an executable JavaScript/action surface with exploit staging indicators such as eval/unescape/fromCharCode, XFA script content, or a related CVE pattern. Benign form JavaScript remains low-severity, but this correlated cluster is high-confidence malicious behavior.
  • ASCIIHexDecode filter (with exploit indicators) medium PDF_FILTER_HEX
    Hex-encoding filter present alongside exploit delivery indicators — often used to hide payload or shellcode bytes
  • 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.
  • 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
  • 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.bitstream.com
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/xfa/promoted-desc/
    • http://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xci/2.6/
    • http://www.xfa.org/schema/xfa-template/2.6/
    • http://www.xfa.org/schema/xfa-locale-set/2.7/
    • http://www.xfa.org/schema/xfa-locale-set/2.6/
    • http://www.xfa.org/schema/xfa-form/2.8/
    • http://www.xfa.org/schema/xfa-data/1.0/

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000070c8.bin
e31f8c8507e52f29008d946a00becde9f839e34cb108985ce66167bf881adafa
pdf-font-stream PDF embedded font (sfnt) at offset 0x70C8 8084 bytes
font_10_sfnt_off000149fa.bin
422bc5698ba5d9d4818f6a2d8b3abca2f723e713b44a15c390139d2c976a1388
pdf-font-stream PDF embedded font (sfnt) at offset 0x149FA 65932 bytes
font_11_sfnt_off0001e85c.bin
7e24ee16c8b09ee74d61445f29c3c0a95abfdf17fc1008606394f159dbd0c106
pdf-font-stream PDF embedded font (sfnt) at offset 0x1E85C 65932 bytes
font_12_sfnt_off000286ba.bin
57e24925bc6bdb98d38e8b4ba3b87f80f75c5e49ea9a522486790d7dc6848549
pdf-font-stream PDF embedded font (sfnt) at offset 0x286BA 65932 bytes
font_13_sfnt_off000324e1.bin
1f068d668b316fcb46f0801be00137fb749cc7fda5ca15e442829d6c303d8f99
pdf-font-stream PDF embedded font (sfnt) at offset 0x324E1 65932 bytes