Malicious PDF — malware analysis report

Static analysis result for SHA-256 88fd4e8b769c97af…

MALICIOUS

PDF

87.3 KB Created: 2021-09-12 23:03:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: ec822ad8a0356c85513895b33cd93845 SHA-1: 599ee90b05449964d785c529174f40f0082decaf SHA-256: 88fd4e8b769c97afad3cd9b2f21521afb9b01fc0eb60cbb908179035375237bc
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to multiple compromised WordPress sites, specifically targeting upload directories within the FormCraft plugin. The presence of numerous disposable hosting links and UTM parameters suggests a phishing or malware distribution campaign. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c47aec08e2---nixuwijelurototilalok.pdf In PDF document text
    • http://nage-z.com/ckfinder/userfiles/files/49074072196.pdfIn PDF document text
    • http://iburgisidimarsala.eu/userfiles/files/limufop.pdfIn PDF document text
    • http://mopron.ru/upload/files/pipazerukanugerinup.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161353492382b0---nanavogewubisoxinen.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/68dfd906bf3d5849993475df972c7211/kelexugalupos.pdfIn PDF document text
    • http://secoinblock.com/upload/files/90777699209.pdfIn PDF document text
    • http://www.prodomasa.com/ckfinder/userfiles/files/mijuvu.pdfIn PDF document text
    • http://houselandia.ru/files/92229173353.pdfIn PDF document text
    • https://nhahangphongcanh.com/uploads/files/16567313507.pdfIn PDF document text
    • http://modern-pro.ru/files/file/werazewavar.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16132ac74ac736---25447535668.pdfIn PDF document text
    • http://pilot-market.ru/new/files/file/sasolejokuvizusazawibazub.pdfIn PDF document text
    • http://gartenstadt-apotheke.com/userfiles/file/81029512896.pdfIn PDF document text
    • https://longislandinvestmentadvisors.com/nini/userfiles/file/nezesudemaweriwapefupexef.pdfIn PDF document text
    • https://whatproperty.ng/ckfinder/userfiles/files/tinovijafikiduxapajetagep.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/zogubu.pdfIn PDF document text
    • http://birizgardenhotel.com/userfiles/file/94774910840.pdfIn PDF document text
    • https://parisnordmedical.fr/docs/file/268326826.pdfIn PDF document text
    • http://www.bash.cl/media/file/gifuwuro.pdfIn PDF document text
    • http://epicridesnepal.com/files/sosako.pdfIn PDF document text
    • http://vijyaiprismcrm.com/userfiles/files/babuv.pdfIn PDF document text
    • https://keralatemples.info/ckfinder/userfiles/files/20149465784.pdfIn PDF document text
    • https://zlataraburmevuckovic.com/files/wabodopunekuzofomi.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139fa415ecf0---71648020698.pdfIn PDF document text
    • https://ud-hobby.com/images/Upload/file/36831494148.pdfIn PDF document text
    • http://jamesandsons.ca/userfiles/file/xifokezavopunaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=offline+slots+androidPDF 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_off0000ee26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE26 18988 bytes
SHA-256: 80ed4da488f30521d9e286ef0c5d57a597688166b1692dc864e7ca5e91d2d9ab
font_01_sfnt_off00011fe4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FE4 10372 bytes
SHA-256: b3c0e33930d862dd5572a409111c287afc85128b323d3ae084d2a0be66541a96
font_02_sfnt_off00013777.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13777 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1