Malicious PDF — malware analysis report

Static analysis result for SHA-256 51c11f4612ed0c18…

MALICIOUS

PDF

90.1 KB Created: 2021-06-27 01:13:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: 46e7e3df396f0883567d507ce8fc2762 SHA-1: a7a90e46477e489dce285baf8ac19c5cacc30999 SHA-256: 51c11f4612ed0c18b15c60b2d510da58f99e9875b038a31dd9c82c9a8d5ab34f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload directories, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and unreadable, providing no direct user-facing content, but the presence of external URIs and link farms strongly indicates a malicious intent to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://clumba-indoor.ru/files/files/ridufogavuzikezazuliji.pdf In PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160742be6b85d8---delitelegokogujerorif.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a077adae09---1744727753.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/a938a4c96be53af9fa05a6dfb068e6ac/wujatasilikisugizeporo.pdfIn PDF document text
    • https://daismene.it/file/79200241861.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1a48b79a6---rofuduk.pdfIn PDF document text
    • https://ksboutlet.com/file/files/46690268211.pdfIn PDF document text
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609f2a250e493---guwilumizevotozedivadas.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160850e5782335---butagajetifujatuvazuru.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/c3068338f7e12ed12cac56d9f99a8562/sowewunufal.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608de7f12998b---bewirasanupufarobugo.pdfIn PDF document text
    • https://prosperitas.be/data/assets/file/57787332809.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a73d00c661f---giremusesukegakibuxa.pdfIn PDF document text
    • https://iwnta.com/userfiles/file/gojobeniva.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608722b36a0e1---72946933640.pdfIn PDF document text
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf3370391b4---63615777635.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088bf15a3f6f---84588332168.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b46a6b9e24d---24626125552.pdfIn PDF document text
    • http://biosite.ru/images/news/file/bixolawojesibinu.pdfIn PDF document text
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/f3e37e15083f5469ec806a8c51256ab3/20018130277.pdfIn PDF document text
    • http://bebelino.ru/userfiles/file/jowojewam.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3befba3e64---36396056444.pdfIn PDF document text
    • http://kusadasidentalclinic.com/img/userfiles/files/31684658251.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/160abaf253f425---12696185680.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=the+eucharist+for+kidsPDF 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_off0000fcfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCFA 16924 bytes
SHA-256: abe0138bf59433ec67fed764c7793d787e0eedb30b6dc21fc9cadc175c6e9a39
font_01_sfnt_off00012936.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12936 10580 bytes
SHA-256: 464f3c85959f7fa72ce402c09148d215aa248ccd1e1063ae51b122e38eec56b5
font_02_sfnt_off00014193.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14193 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1