Malicious PDF — malware analysis report

Static analysis result for SHA-256 275f8f4f4038035e…

MALICIOUS

PDF

82.0 KB Created: 2021-07-04 20:58:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 55dfc665c28bbbb79122943da68700b2 SHA-1: 3893d900faf39fa21d6c2723a59b2b6283390ee2 SHA-256: 275f8f4f4038035e69fa324955936b30106b313dba47c1746fff99db85946fae
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting it's designed to lead users to malicious content or phishing pages. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution via these links. No scripts were extracted, but the structure and URL patterns are indicative of a link farm used for initial compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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=c%23+coding+interview+questions PDF link annotation
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/29a2q4bpkcbbgp0e4fa2ruca2t/xokow.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d51c5e28686---36246494635.pdfIn PDF document text
    • https://tarzminder.com/resimler/files/vumeni.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/98odtlhm7cu96gflt9g5o7ufei/lilowinakibavir.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/4c09rj2dis7m7jo5a5v9jj3411/zefulajarisulewareza.pdfIn PDF document text
    • http://bantinnhadat.com/users/files/99161424585.pdfIn PDF document text
    • http://i-dron.cz/data/file/besugoxosijoburo.pdfIn PDF document text
    • https://hojoairport.com/images/file/24125823507.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b04b6bcb6a9---13100440212.pdfIn PDF document text
    • http://to-tuong.com/media/ckfinder/files/26754742203.pdfIn PDF document text
    • http://humboldthighclassof79.com/clients/1/19/19f040aad945c40a0acbd79abd3dc6cb/File/tawiduvatosoreluba.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c713f2c2290---75003466793.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/93984575036.pdfIn PDF document text
    • http://altinay-law.com/images/file/12628783794.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/160ae6834bce41---pijep.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c03ab82e6ae---85840414864.pdfIn PDF document text
    • http://christschoolblr.in/userfiles/file/39685879552.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607c55a857bc6---nudabufodaselipesumigepe.pdfIn PDF document text
    • http://imaginove.eu/data/Files/75505848996.pdfIn PDF document text
    • http://ceskylakros.cz/userfiles/file/zawodibewelofatozelorit.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/875700aac40948636ae472df67aeaaaa/34973963404.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/gamokinolevefideje.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/346kih1m49f06mil25ggbbi6g5/pediwubezu.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/17a9296813ed22c921efb3669c08a264/runimikeselemuwevupir.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160710c534a50f---rijirulekivesisokewig.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/ac480a236a45db7e72494b223b2aa93c/kukotapevapubodujovuzowo.pdfIn PDF document text
    • http://jakebenmd.com/clients/0/0e/0eef9d569b11303d075d19626cc6f958/File/43115388773.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_off0000e3d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3D9 17384 bytes
SHA-256: cd8e162dc0fa5a40cb9e9f14dcec96e9f10ee38cda9f04de3691822963ccfcd8
font_01_sfnt_off0001112d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1112D 9104 bytes
SHA-256: fe4a9ad32d6d12da45ce8861a1e6e511df5579fd33367a5c4d1c9e774d301804
font_02_sfnt_off000123fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1