Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a35af230597379f…

MALICIOUS

PDF

70.3 KB Created: 2021-09-04 04:55:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 739869a5d0523335315215f04569d061 SHA-1: c470bf5e5d810f0995f7aac58139d455701dc110 SHA-256: 9a35af230597379f0e323edae1fe6e0ccc4ab96a36a362240f39d47b57639058
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised or disposable hosting sites, likely for phishing or SEO abuse. The presence of external URIs and link farm indicators strongly suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.weilandensemble.nl/ckfinder/userfiles/files/15802132251.pdf In PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e2cb10f79f---salulemaruwegusaxukax.pdfIn PDF document text
    • http://ilkemymm.com/image/files/20093308412.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/03a21abf8811a9acaf2bf8f30a86d767/zojukovawawinawuponefobav.pdfIn PDF document text
    • https://glycocalyx.nl/userfiles/image/file/49546057989.pdfIn PDF document text
    • http://bundoreh.com/fckeditor/files/file/penikavasisidakif.pdfIn PDF document text
    • http://michaelwilliamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/52907768789.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/1607a765d55d70---xemuwiginolovukigusiv.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bf32204d702---92680355172.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/q2n83nato9i4ur2mjdppvp9n35/pimixe.pdfIn PDF document text
    • https://triatlonshop.cz/userfiles/file/wimajivarufubitedomow.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/6e10a6b499b18f281effdca8f33c8542/pinizekipupe.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160e815a50b785---26625276035.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///jegizeridaba.pdfIn PDF document text
    • http://taemyung.com/data/upload/file/dikitogulesegududesumam.pdfIn PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a710f6cf2ee---60402670589.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/92744136779.pdfIn PDF document text
    • https://rockyshairsalon.com/wp-content/plugins/super-forms/uploads/php/files/lef4q7qohrb91vekiskrli3ljs/pemirujugo.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160812a444905d---74405133233.pdfIn PDF document text
    • http://vswet.ru/f/95024628986.pdfIn PDF document text
    • https://pianoinprimopianofestival.com/uploads/file/towopupuvidalit.pdfIn PDF document text
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609637bd2fd2f---kesijewop.pdfIn PDF document text
    • https://vansuloi.com/uploads/userfiles/file/45370844899.pdfIn PDF document text
    • http://presssimayeshahr.ir/pic/file/juwozezuxegadowiz.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f623ee22a3f---73739687780.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=briggs+and+stratton+vr2500+pressure+washer+manualPDF 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_off0000b44e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB44E 11520 bytes
SHA-256: 980224e049dbe09ac8170c5c4315186a9dafc4f0119f5b559081e8d92518b2f8
font_01_sfnt_off0000cf57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF57 14924 bytes
SHA-256: 9ec57fbeba22e5cef043c00aabf960fe1368207d283aaf6900cd30a37d10dfc9
font_02_sfnt_off0000f36c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF36C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1