Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb6b9736b2146cf8…

MALICIOUS

PDF

97.6 KB Created: 2021-07-08 12:53:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 265622a697408b26be79304e27517511 SHA-1: 72d27f426369d27f9881b80d22b46391d1eac990 SHA-256: cb6b9736b2146cf8f65225d700625bc6d584954a5d73042166b3179151228646
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, likely serving as a distribution point for malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, classifying it as a phishing trojan. The presence of numerous external URIs and compromised CMS upload links suggests an attempt to lure users to external, potentially malicious, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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://ambientltg.com/wp-content/plugins/super-forms/uploads/php/files/f78d7832389b26b727efed35b0d01869/xanamepofab.pdf In PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160ab9115d74cb---maxiwa.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b08a744f816---76267772775.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/p74271tqh7lmv1aq5i4ka46dk4/40446911389.pdfIn PDF document text
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/5aed6ad08d4bec8a9769cb9d2242df76/tagamit.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609740bb1be2e---97900583576.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ad977e80060---kogafowuvexut.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/8e9b016eeb096e156edc302ac9f938fe/fujakosedu.pdfIn PDF document text
    • https://mmszke.hu/files/file/dudawodegu.pdfIn PDF document text
    • http://naasschoolofmotoring.ie/fckeditor/userfiles/file/42653258394.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d8d09c685de---42350449356.pdfIn PDF document text
    • http://bindashnews.com/userfiles/file/6281134346.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/99994351648.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a22703c63a---barajobufotijizok.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea8062c730---jixoxabesew.pdfIn PDF document text
    • https://www.carrentchiengmai.com/files/wufutube.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/e16268a3d5fe6afb5063cbb71dff7eef/9036378498.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/6fbcaa0515ee71c0105816c4f9e24ec0/dasilovegagomusof.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/75109663b0134f1f31df5c205829f792/56925190172.pdfIn PDF document text
    • https://thedestinbeachhouses.com/wp-content/plugins/super-forms/uploads/php/files/f0f9dbf9ecf1c01d3db7048500b24e19/jovosogenisuwedixefilujop.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/9f3b96dc38559017c8d8d662f202704f/91665254678.pdfIn PDF document text
    • https://mrmobilewebsite.agency/wp-content/plugins/super-forms/uploads/php/files/2776a1b78b053abf14623baff4d747a0/42428307468.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cab567349ed---kigotinujudud.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/75712036d40e826c7ff9d27bee69d235/waruberofebuxan.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160abd02e76b2f---tagibofal.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/5e12fcf6dbf588c0fa8170e621dcbb86/56791810978.pdfIn PDF document text
    • https://hssipm.com/wp-content/plugins/super-forms/uploads/php/files/322feef929ac1cef8c92e5f46260d03e/26111516258.pdfIn PDF document text
    • http://unesco-mediain.cz/fckfiles/file/90661932876.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=lease+with+right+to+purchasePDF 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_off00011712.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11712 18060 bytes
SHA-256: 5e79e01d410bde3479043d7f684acb984b1080d587b8c1388780615fb0859958
font_01_sfnt_off00014693.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14693 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015eaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15EAA 10648 bytes
SHA-256: 99f2e223f3db9bfa2f008fe144537bc41ac790cbbf5a86380c0505cf79e35686