Malicious PDF — malware analysis report

Static analysis result for SHA-256 51ff1c4930462c21…

MALICIOUS

PDF

89.7 KB Created: 2021-06-27 19:55:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f4bc9c753a00fe409541521a51a801e0 SHA-1: a1e94e56854327a5e3c93ed88a415f672cfc0b33 SHA-256: 51ff1c4930462c21337490936f228a0f1a655853a85423d9305c1f15c82b49fb
156 Risk Score

Malware Insights

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

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress upload directories and disposable hosting, indicating a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, suggesting it's not intended for human consumption but rather as a container for these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://eska-lift.ru/userfiles/file/davolujomuseraze.pdf
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9545de7bf1---9125315478.pdf
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/db8cbca8cc6fa5d5186ec22c008256c7/vumume.pdf
    • http://shs1977reunion.com/clients/41590/File/gugudodevojepe.pdf
    • https://www.temsilcifirsatlari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608451bde2a64---23914638474.pdf
    • http://business-plan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/gemujopatoparipodoposaguj.pdf
    • http://florylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fikupusoxiwosivig.pdf
    • https://www.ideaklinik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160702e3a93e32---38225393952.pdf
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/298dbd8e453123efd052293b9f834c31/vakabulokemo.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073bf6351420---29167476663.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bace6261ad6---regukuturifapofof.pdf
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/b1d29a77d39dbb9748fbcdb5406cb888/garawatifabovedazir.pdf
    • http://tipsclubcr.com/campannas/file/mavow.pdf
    • http://przychodnia-felinskiego.pl/uploads/editor/file/kamebivodajep.pdf
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607364090d45a---delofagizirasokejinojejex.pdf
    • https://www.deuba.info/wp-content/plugins/super-forms/uploads/php/files/r3864a2un29jvsno5n6scne1c7/82247479853.pdf
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6bf52e3937---10190974406.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/b770916fc0816f67a987cb4cbc32dafc/69002842377.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe96adc499---24904295272.pdf
    • http://qiuyutv.com/userfiles/files/20210620025812.pdf
    • http://guowangcable.com/d/files/62837579055.pdf
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/5b4u9gims0j2dtnmo35630bo32/13542282504.pdf
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/9faht71noadlgb84qvd0j6t9ek/41160029366.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=god+creating+the+world+in+7+days
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fb5b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB5B 16792 bytes
font_01_sfnt_off0001136d.bin
2b54f8f1e854111045637c28242c9b772cb412fcadf0ead251f6f999f567a443
pdf-font-stream PDF embedded font (sfnt) at offset 0x1136D 17172 bytes
font_02_sfnt_off00014060.bin
3cd88634604aaad72b4e237b16973e6d1751b156e50d9af8e5f10dd4657d937a
pdf-font-stream PDF embedded font (sfnt) at offset 0x14060 10936 bytes