Malicious PDF — malware analysis report

Static analysis result for SHA-256 813160fde457f252…

MALICIOUS

PDF

83.4 KB Created: 2021-07-13 19:52:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 05090fed5dfebd07d60d3a1f3535783b SHA-1: f85061e2fd023a33e0d843b83e586da9ca3cf780 SHA-256: 813160fde457f252aafb132ac01e2430895d53926a9574ec4722b83d76d809df
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links indicates an attempt to lure victims to potentially harmful websites, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://medvor.ru/uplcv?utm_term=calculus+for+ap+a+complete+course+answers PDF link annotation
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607f9585e586e---75603198193.pdfIn PDF document text
    • https://dycmc.com/DATA/upload/files/202106230221416692.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1607fff9b6623b---4629832626.pdfIn PDF document text
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/407683f8fc726d08c1ca13cd517f9ad9/zigusafowonusomiwa.pdfIn PDF document text
    • http://nesemlak.com/test/images/uploads/files/wupositoxef.pdfIn PDF document text
    • http://abovomedia.hu/_user/file/40426586200.pdfIn PDF document text
    • http://orkoien.com/userfiles/files/25956536490.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160ab80a347a2a---52227753765.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/7a432e6661f04832acd475091f391417/10975051213.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfd51582d07---11385160731.pdfIn PDF document text
    • http://aldara-latinoamerica.com/userfiles/file/74813053095.pdfIn PDF document text
    • http://safeabortionnepal.com/userfiles/file/pepenitenibakuvu.pdfIn PDF document text
    • https://systematix.pl/userfiles/file/62938472771.pdfIn PDF document text
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/415vhv0l1pnl7i58qki5hif45r/duxitifanulozexebu.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/8c455d44e484c27e9c2211783459a702/favozupujasuzubanulo.pdfIn PDF document text
    • http://hebertfamilyreunion.com/clients/3/32/3272330ca4c68e8b1120eb7f178c7a05/File/2345239905.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3464192389---12761470395.pdfIn PDF document text
    • https://marigabung.com/contents//files/gekoreji.pdfIn PDF document text
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/56fb74c5dd7ce213c4263e2fba3a138a/degotonume.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/96108054673.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608758a8eb3fa---zevagesi.pdfIn PDF document text
    • https://businessservicesuk.com/userfiles/file/wefilugomulazejo.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4677205499---87949959252.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a65983b4d71---36361527795.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b32ad0ec2a---tivagisow.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/jomimerolaravumuvezoxebo.pdfIn PDF document text
    • 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_off0000df3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF3B 10764 bytes
SHA-256: b13544ac20523c03e5d998f2e3ca0a3a171461b398bd264981fc11007aa0b60b
font_01_sfnt_off0000f822.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF822 17504 bytes
SHA-256: 46e8c47fd920940dd42a2a0a2a132c85ace480142f64db8842652b5ec039d6c6
font_02_sfnt_off00012629.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12629 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1