Malicious PDF — malware analysis report

Static analysis result for SHA-256 e9a8f8192da0d347…

MALICIOUS

PDF

100.7 KB Created: 2021-09-07 23:19:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 8a57c26a3b075083a7917cf7a79b33c7 SHA-1: cec7f546fcd597205d98a287d983c7d8126c1638 SHA-256: e9a8f8192da0d347bb09ac5b9fe1542e73c9b309b9c00c6438075fe4643f0fd7
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, and the presence of link farms on compromised CMS platforms suggests an attempt to distribute malicious content or phish users. No scripts were extracted, limiting the analysis of direct payload execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9923

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://staresecurity.com/userfiles/file/47623599084.pdf In PDF document text
    • http://sushimura1.com/uploads/files/kerolope.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/pgmq9d3hp8855am3vj4cagutn3/77289647294.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/16073d52600ce6---xugux.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/204ac585a81922358d9d890038db225e/87007382469.pdfIn PDF document text
    • http://avstralianature.ru/ckfinder/userfiles/files/20808030339.pdfIn PDF document text
    • http://babamoleskine.com/files/file/59502921112.pdfIn PDF document text
    • http://chocoenglish.com/_UploadFile/Images/file/29587861879.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5abdd46b49---vixepusujezigefobiburid.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160f8abd8150fb---61777047301.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/445b2be156d598d3c868a51cb81af3fb/turijavadapomituxivine.pdfIn PDF document text
    • http://lapawan15.com/shop/fck_file/file/76162689589.pdfIn PDF document text
    • https://xlspandoek.nl/userfiles/file/16575174487.pdfIn PDF document text
    • https://qfse.co/images/uploaded_files/ckfinder/files/1627557372_52ede88c85.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/3e9ab36e750e7da58746a184b78116b3/87632170080.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096928c69041---20795017941.pdfIn PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3ff9cc75a8---57725939798.pdfIn PDF document text
    • http://przystaneknida.pl/data/aktualnosci_imgs/file/84587459670.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/16083f0e9b70d6---26612394615.pdfIn PDF document text
    • http://ligneus.hu/upload/file/nijoxunavisawogerojefe.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/krc5glc77avdi60naf7i0uj7p6/70507067202.pdfIn PDF document text
    • https://washlounge.in/ckfinder/userfiles/files/27545228940.pdfIn PDF document text
    • http://podiummoda.ru/userfiles/file/3038893559.pdfIn PDF document text
    • https://speculatio.in/userfiles/file/65679229892.pdfIn PDF document text
    • https://postelezmasivu-zlin.cz/ckfinder/userfiles/files/74588162870.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=tp+link+router+wr940n+manualPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011e27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E27 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001363e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1363E 10852 bytes
SHA-256: f685c9b36c5ae4893c1ceb9752faf44cff380af9f9e5046096d61c2b5f2649df
font_02_sfnt_off00014f5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F5B 20564 bytes
SHA-256: ca7e6d88c2124f427997a0e0e996ca95bd5b7fc6d08f30b16238212e27928d00