Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca527bf3cad0146d…

MALICIOUS

PDF

93.7 KB Created: 2021-08-15 04:19:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: f0da3500ba580342f4b4fa582e9b0ea3 SHA-1: b28ea1ded0068b9f2b6791205f0aeeb80db0e9aa SHA-256: ca527bf3cad0146d4bd849bb12255c981c514572a1a5e14347fb52622b9e8eef
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with several pointing to compromised WordPress upload directories, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://fixafilm.se/userfiles/file/45032513830.pdf In PDF document text
    • http://ahs1978hounds.com/clients/0/09/09313dc2b2b2138818c22350edca9cf7/File/32257590384.pdfIn PDF document text
    • https://cqc-material.com/app/webroot/userfiles/files/kamanevadane.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/f6ec92c29284b1de1815efe857bb4a9c/gulaxa.pdfIn PDF document text
    • http://dogoxuavanay.vn/uploads/files/kixike.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf28623fd44---farabomiraru.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607c033bd3277---53090759792.pdfIn PDF document text
    • http://materialdeestudo.top/userfiles/files/gapesag.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/monosawapigotanifomoko.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab60d3ff5e---jozugerotapiliwarezisoku.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609dd79b5c038---suzifar.pdfIn PDF document text
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/5dbbd9047caeae530df1fb8c99670e76/modinowitanigiwafodofi.pdfIn PDF document text
    • http://macautemple.com/userfiles/file/betogixaxuliku.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/be7aa8dc98b898ef6371f748aebaaf26/pozowofagosaxisa.pdfIn PDF document text
    • https://pergamine.com/ckfinder/userfiles/files/93386969485.pdfIn PDF document text
    • http://farmina.ru/uploads/files/74436182052.pdfIn PDF document text
    • https://pakistanchristiancongress.org/userfiles/file/tagibej.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/99297869389.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/92198001017.pdfIn PDF document text
    • http://chapmanhighschoolclassof1968.com/clients/c/cb/cb1fed5110c07f199f416a264ee6943c/File/52164931051.pdfIn PDF document text
    • http://birzebbugastpetersfc.com/files/file/kabixowurejutugojogu.pdfIn PDF document text
    • http://luxcottage.ru/stroykamen/userfiles/files/46913899249.pdfIn PDF document text
    • http://geodez.com/pliki/file/78267137202.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/5961961gduejm38kv687tu1f43/79673476311.pdfIn PDF document text
    • http://ih-consultant.com/ckfinder/userfiles/files/rarizotupuzexemofudo.pdfIn PDF document text
    • https://anup.bo/images/files/50457852317.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=income+expense+excel+templatePDF 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_off00010b54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B54 10396 bytes
SHA-256: 992ab56eadc2234014d5fffd6218ef5b7b629e2c6213c1ea57baa3fb30c6dca9
font_01_sfnt_off000122e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122E5 17512 bytes
SHA-256: 9a6d9a566aa88e3bf26043bb47f3997ff1b7a28bd640864ae993d8f38bdd65fc
font_02_sfnt_off000150b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x150B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1