Malicious PDF — malware analysis report

Static analysis result for SHA-256 d61630e42a200bd1…

MALICIOUS

PDF

82.5 KB Created: 2021-09-09 04:15:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3669e36dcfba0b568f11d91bdc27da93 SHA-1: 02dbd3bdb980fc7b737c227d8796e69d85526a1d SHA-256: d61630e42a200bd1771d41752583dfd34656a8748bfbbfee1f0a263521cea993
156 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 CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://marlin-aquarium.ru/ckfinder/userfiles/files/21651565299.pdf In PDF document text
    • https://callmarkinvestments.com/callmark/files/528620160.pdfIn PDF document text
    • https://ajansnigde.com/resimler/files/84624359067.pdfIn PDF document text
    • http://sinocelltech.com/filespath/files/20210902041645.pdfIn PDF document text
    • https://debo-fit.be/userfiles/file///kugegumamesonibozapiwe.pdfIn PDF document text
    • http://phutungquanghieu.com/app/webroot/files/ckfinder/files/59450429162.pdfIn PDF document text
    • http://allycatering.com/userfiles/lobevizaropekimud.pdfIn PDF document text
    • http://congluc.com/upload/files/63936340352.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161387508e1b8d---20985724564.pdfIn PDF document text
    • http://aesg2edcv.handylover.com/upload/files/loxexetep.pdfIn PDF document text
    • http://icr34.fr/icr/icr34.fr/www/files/files/nelofexebivojanavoli.pdfIn PDF document text
    • https://afritransport.com/app/webroot/files/file/26712943593.pdfIn PDF document text
    • http://wwpokebar.com/uploads/files/57050604909.pdfIn PDF document text
    • http://bafiti.com/sklep/userfiles/file/maraluwavodamemori.pdfIn PDF document text
    • http://miraesusan.com/ckupload/files/48175516434.pdfIn PDF document text
    • http://www.eau-msu.ru/ckfinder/userfiles/files/73175409508.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/b389b2a7d3c6171a7630c5ce71252832/67925376095.pdfIn PDF document text
    • https://galerieportelouise.be/userfiles/files/turonuvese.pdfIn PDF document text
    • http://sunriverps.com/data/editor/file/kaputidi.pdfIn PDF document text
    • https://hk-delight.com/UploadFiles/file/juwisekajuruku.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/da52b4ab49b0b3bf38c30fc62f12d6c8/80531868523.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=my+magical+girlfriend+mod+apkPDF 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_off0000d29a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD29A 21816 bytes
SHA-256: 95d08df5442d7b560af399b4bfefd7914e5d429e5c1980c0bc29ece2634e2a66
font_01_sfnt_off00010b97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B97 10896 bytes
SHA-256: 3298d87a8a42b085e43dc242ecee6b50ee7a07310ff5d5f2ea6ce1e7e526cd5e
font_02_sfnt_off0001248c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1248C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1