Malicious PDF — malware analysis report

Static analysis result for SHA-256 cc3c754fd88d619b…

MALICIOUS

PDF

92.0 KB Created: 2021-07-02 09:16:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 491e90e1602b0cce4a3ed90f5ef90754 SHA-1: 4c169490380e6d9ffbdb3cdacda3db3b947274f5 SHA-256: cc3c754fd88d619b5fc092ac6abeeaa5a45a44c1659972e5432844be3103010f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised WordPress upload directories. These links likely serve as a distribution mechanism for further malicious payloads or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bd9eded77e5---73561715590.pdf In PDF document text
    • https://www.nosolodespedidas.es/wp-content/plugins/formcraft/file-upload/server/content/files/160810917e5308---60868069277.pdfIn PDF document text
    • http://meadclassof1991.com/clients/c/cc/cc689d7a74a098ef67b43942063c7ff9/File/sudijawelipetabo.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/64dc4ed6747176e16ce13b481cd553f9/ravuvujupumivepaxemovijew.pdfIn PDF document text
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/160af69d204fef---31492812938.pdfIn PDF document text
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afa62486da9---22816725272.pdfIn PDF document text
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/8296b48c1bac6e9771f839a91c4da370/xafifepabogitawiweriz.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160d7aa2053aa1---gipareruligonagujud.pdfIn PDF document text
    • http://zulassungsservice4you.de/bilder/file/wiserotavoxujorarefir.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/c5aea19511532000b81ff7ac4a65cab7/97956895262.pdfIn PDF document text
    • https://fallsplat.se/file/7615751171.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/ac0dcdc5d5a17d5664f0e80fad8da4d2/xujutegaxumo.pdfIn PDF document text
    • https://noddy.nu/images/file/birutipebenuzemovin.pdfIn PDF document text
    • http://cityhigh78.com/clients/2/2d/2ddbae4fb74c169819b3574d76e4e264/File/33005046464.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075b0822e4c4---88004113558.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608eb74e65227---98449882816.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160899f51e95e7---10192861578.pdfIn PDF document text
    • https://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/8a293341afd1473e6df1133a8d9cc855/58584760083.pdfIn PDF document text
    • https://afd.me.uk/wp-content/plugins/super-forms/uploads/php/files/5ldebjj6bfpl9lqe544mpc4u1j/buzedefotekegujopif.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb9c9e0cbfb---tipodurubudux.pdfIn PDF document text
    • http://goodtraefarm.com/ckupload/files/sixotob.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160829a2505f1d---75007717554.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=a+fistful+of+dollars+trilogyPDF 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_off000105ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105EA 17656 bytes
SHA-256: 186e727eddd2f1777f1675349a308a44ce4d5ac2ca01947643eead0e3e8983fb
font_01_sfnt_off00013338.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13338 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014b4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14B4F 10488 bytes
SHA-256: 879ef061c00673d53e3715e05f40357ace551dc9dfb159f47c9fc4d05d4545c9