Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cadb38a840e48a1…

MALICIOUS

PDF

68.6 KB Created: 2021-09-27 21:06:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 176672bbe3e267e8af729acace01eec1 SHA-1: 5e5ef37b07710d9feaa4766d2bbd8621f99808bb SHA-256: 3cadb38a840e48a1a6cc4e8df7129b125ec143fcee496b575737411a2e8bfee0
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress uploads and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of link farms and the use of compromised CMS uploads suggest an attempt to obscure the true destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/161492280204aa---lojexekejakulufuda.pdf In PDF document text
    • http://aias.pnu.ac.th/ckfinder/userfiles/files/genanuwetodajijovi.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/sudabadu.pdfIn PDF document text
    • https://777mto.com/contents/files/bugupofotuwobifozer.pdfIn PDF document text
    • http://chanhbon.vn/media/ftp/file/50170570679.pdfIn PDF document text
    • http://abwfinlay.com/uploads/files/nerina.pdfIn PDF document text
    • http://portaldo.eu/contenuti/upload/file/56858375681.pdfIn PDF document text
    • http://portalinmobiliario24.com/uploades/fckeditorfile/masujumesedisesiwe.pdfIn PDF document text
    • http://geologocarmignani.com/userfiles/files/vafuxosagenuke.pdfIn PDF document text
    • http://www.immo-uno.com/ckfinder/userfiles/files/51681001622.pdfIn PDF document text
    • https://gogift-it.com/userfiles/files/vibusudaw.pdfIn PDF document text
    • http://sklenicky-obchod.cz/web/admin/fckeditor/userfiles/file/67682750234.pdfIn PDF document text
    • http://terhautz.com/upload_files/files/genoginuzotam.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1613fada6468a0---rofekuzivubijikelebu.pdfIn PDF document text
    • http://kondicionery-shodnya.ru/upload_picture/file/68213392248.pdfIn PDF document text
    • http://siblom.ru/files/upload/file/68110810536.pdfIn PDF document text
    • https://biblioteka-koneck.pl/ckfinder/userfiles/files/22700757476.pdfIn PDF document text
    • http://17njl.com/userfiles/files/85908451069.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/16150f22b07f8f---nimosefav.pdfIn PDF document text
    • http://dakmoto.cz/obrazky/file/bivejapomumepos.pdfIn PDF document text
    • http://aihyang.com/userfiles/file/peboduwu.pdfIn PDF document text
    • https://www.verimevzabavu.cz/ckfinder/userfiles/files/54183925486.pdfIn PDF document text
    • https://teater77.nl/userfiles/file/fokabupegaxuwapajegukeni.pdfIn PDF document text
    • https://volpatoebrum.com.br/_common/admin/scripts/ckfinder/userfiles/files/fagoragefamamuj.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd62f3c178---kovidululusawop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=charlie+munger+almanack+pdfPDF 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_off0000b007.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB007 14384 bytes
SHA-256: 2f125bb045a6b385c1d02ea77741be2652b0de9a2cd47264031b57955319f3c9
font_01_sfnt_off0000d416.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD416 10904 bytes
SHA-256: c2c98b413bba41d96d2695b144267cadb1b19d2cca5f597d3a7470471ec91c46
font_02_sfnt_off0000ecdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECDD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1