Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c6d3390cf3e5afe…

MALICIOUS

PDF

93.3 KB Created: 2021-06-27 18:56:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 25284bdd7d37259395a5eae691e98858 SHA-1: d11c27bb96cfeb65024a32c9dfb5bb715e4d2da5 SHA-256: 7c6d3390cf3e5afe7c227e6bc46c2c11bee51b6907a64cd3b743bbb40f246892
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It contains numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further obscuring its true intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9924

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://wastran.ru/uplcv?utm_term=app+for+learning+quran
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/aammvufr7u6tp265upefkv1f44/sopipeworipise.pdf
    • http://peaceinsrilanka.lk/userfiles/file/67607114162.pdf
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1607140b4424f1---68417181479.pdf
    • http://straub-online.ch/userfiles/files/tupolovasakuwixilo.pdf
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/e77a069678a4343a0165818b9ff3dd9c/91545803141.pdf
    • https://bouveau-consulting.com/userfiles/file/seturuviluzovofo.pdf
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/4da91092cb0b6651aa2391e227102698/robabegegex.pdf
    • http://fritz-fahrlaender.ch/download/51765176841.pdf
    • https://lesfeesdelhetre.fr/upload/files/dakapexam.pdf
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/9de304d971aeb5ffd7055cacb6471e18/ratolojevuk.pdf
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b7e9c0030---menimedobidonijekafibemoj.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160abf992b5ec1---64157652856.pdf
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ced886a63a8---jesefawiforanopir.pdf
    • http://imaginove.eu/data/Files/savun.pdf
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/85dea02add022ae1b9691fb657030231/lefuneparanave.pdf
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/0b0a961f18acdc5a7b124fe005203539/2571917096.pdf
    • https://balaji-technology.com/userfiles/file/fegez.pdf
    • http://dientrotiendathc.com/media/ftp/file/mozopudujewijoberas.pdf
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1609bb6d6c54ab---zamazewuvunazafunenu.pdf
    • http://onlineticketreview.com/images/file/vutavebegawabituwanug.pdf
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608b8acb461f2---dajomixudive.pdf
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084f7d75e743---25244820794.pdf
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609156347bd6c---40086861152.pdf
    • http://ahcxdq.com/uploads/file/041245497466.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab63f1be2b4---lodotug.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f10b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF10B 16792 bytes
font_01_sfnt_off0001091d.bin
068e7d4dc28d4b19802b8f256f91c914d51dff9f62a0ef02231fc0972e782dd1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1091D 17196 bytes
font_02_sfnt_off0001359d.bin
09208a70865be9576b9b6ebef023e073c1883dbe779349fc01fdf1ca505e0f66
pdf-font-stream PDF embedded font (sfnt) at offset 0x1359D 10492 bytes
font_03_sfnt_off00014d37.bin
c59bd96601ce80b1acf776603f4e52f919d50d4b15f05afde156167635af0f01
pdf-font-stream PDF embedded font (sfnt) at offset 0x14D37 17004 bytes