Malicious PDF — malware analysis report

Static analysis result for SHA-256 85ac25e367e2fd4c…

MALICIOUS

PDF

93.9 KB Created: 2021-08-10 09:53:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 1dfe0af17966d8cbd765a1e2fe693866 SHA-1: d0d62c2085e8343fd0e7639f50c04c7b06d29434 SHA-256: 85ac25e367e2fd4cabbd210590b3b8ae1a0b8142f019236e566d1ce11d3e036d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to obscure the ultimate destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of an attempt to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 https://smidgel.ru/uplcv?utm_term=series+and+parallel+circuits+worksheet+answer+key+pdf PDF link annotation
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609840ad9b8bb---82266407535.pdfIn PDF document text
    • https://pendekaremas.com/contents//files/vojebanezitavigoruveteja.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607e992d0b809---pasurifoj.pdfIn PDF document text
    • https://hospvetcentral.pt/site/upload/file/87910480465.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/fa9ec3c521b08863ee58032fe1fe631f/54865671024.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f457fd4071---63581818311.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609931a020abe---64006413873.pdfIn PDF document text
    • http://goergenpainting.com/clients/0/0d/0d1038892961fdbf96b6a8e7e8daca8f/File/todujorefatobadomodat.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/430a470ee483e1d1c7ba9c8f2644ee45/83442787918.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e46854ee0ac---42774490325.pdfIn PDF document text
    • https://mattress-leader.com/media/44020033233.pdfIn PDF document text
    • http://wib24-admin.de/uploads/file/dudofepefi.pdfIn PDF document text
    • http://agrion.org/upload/fichier/balenatura.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bb1ef70c6b---wuwelatefiwidimifonu.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ab80fb41c53---gujebukumixo.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/1770d451de2ea9abb32db97fffed2764/tulake.pdfIn PDF document text
    • https://digireg.cn/upload/tewonekajopuvopadirawamag.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/31qouobea68mb6enk2tir8rvnl/bibanixilokagelugutel.pdfIn PDF document text
    • https://aykutemlak.com/upload/ckfinder/files/35622086466.pdfIn PDF document text
    • http://conflictfreeelectronics.com/ourprojects/chowki/UserFiles/renuka/file/petutowuva.pdfIn PDF document text
    • http://sjhrz.com/images/upload/File/keguwopelogu.pdfIn PDF document text
    • http://dieta-plus.pl/userfiles/file/vutafizenudixogamepavu.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16077a378279d4---ketovajanubolevitudile.pdfIn PDF document text
    • https://10glazsikeyrosa.ru/file/14341501661.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5fb63a5ae---36110565869.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_off000107d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011fe9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FE9 17564 bytes
SHA-256: d0da4b99a4b273dae4c88f1a0b3351cde3cfd278b7519eb4d8ddc3544f6a4c9b
font_02_sfnt_off00014dfe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14DFE 11184 bytes
SHA-256: ab0a6fa43eb5a31f07bd79833ec7967c12795908393166adc6e320ef51128d41