Malicious PDF — malware analysis report

Static analysis result for SHA-256 d86485e4208b987b…

MALICIOUS

PDF

82.0 KB Created: 2021-09-23 04:19:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5c292c8254f80c860f7568c7b93705be SHA-1: 2c365578594c6caaae3bf52d8e32fa3ca4504992 SHA-256: d86485e4208b987b715e67056abb092546d88d1bd7aed592385c26aa20c6f0be
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 numerous domains, many of which appear to be compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery via these external links. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9797

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://smidgel.ru/uplcv?utm_term=handler+postdelayed+kotlin PDF link annotation
    • http://izeninfo.net/admin/upload/files/zadibipanuk.pdfIn PDF document text
    • http://vet-spb.com/userfiles/file/titomelerejoriza.pdfIn PDF document text
    • https://getracemirates.com/userfiles/files/11131858300.pdfIn PDF document text
    • http://www.s4b.nl/upload/files/boxejusaro.pdfIn PDF document text
    • http://losmarinoslanzarote.com/marinarubicon/admin/file/9856405284.pdfIn PDF document text
    • http://xn--80aatg4aaaddkhfhbf3evf.xn--p1ai/ckfinder/userfiles/files/46901985397.pdfIn PDF document text
    • http://pokewaveanaheim.com/uploads/files/47461238055.pdfIn PDF document text
    • http://rebeccaosborne.com/uploads/33863806772.pdfIn PDF document text
    • https://manenshop.com/upload/files/dinuluturagazedirazumaje.pdfIn PDF document text
    • http://nova-auto.com/upload/serabexe.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fa9edb3967---tobenew.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/jafatomejanolexaw.pdfIn PDF document text
    • https://futuresbuilder.net/dayafter/uploadimages/newsimages/file/14241490898.pdfIn PDF document text
    • http://audyt.rowerowaszkola.pl/imgturysta/files/piledesuwizagox.pdfIn PDF document text
    • https://kozhikodedeaf.org/admin/my_files/file/ruduj.pdfIn PDF document text
    • http://bckbytow.naszbip.pl/img/upload/files/lazesew.pdfIn PDF document text
    • http://giprozdraw.ru/ckfinder/userfiles/files/40357168168.pdfIn PDF document text
    • http://liveranigioielli.it/userfiles/files/womimuno.pdfIn PDF document text
    • https://faktxeber.ru/resimler/files/kexafesomejubunolomumoseb.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614bb7b993985---xitukunepaxogipipaliguw.pdfIn PDF document text
    • https://hbphoto.ca/resimler/files/roturorujopoxasabifovebox.pdfIn PDF document text
    • http://kirakuramenandsushi.com/uploads/files/gomuxiveg.pdfIn PDF document text
    • http://www.ssc-ras.ru/ckfinder/userfiles/files/6148655946.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/161459f2b26589---80457037184.pdfIn PDF document text
    • https://rijst.nu/userfiles/file/jiwokasuje.pdfIn PDF document text
    • http://andrenickels.de/ckfinder/userfiles/files/xesovidoluberoko.pdfIn PDF document text
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c109.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC109 10584 bytes
SHA-256: 529cb8f639469d185803ffb18c30c10724a219573961d9f86499ebf714438748
font_01_sfnt_off0000d940.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD940 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f151.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF151 16244 bytes
SHA-256: f74afd43c04b882caf2cf4abe35f4f287291876a5effbe79c277cf827c8612e5
font_03_sfnt_off00010748.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10748 20016 bytes
SHA-256: 6485f7a8f6c60eb985d6fe27dca557aa9c9448ce018ee8837a1baca2e17fcca0