Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b85a19143ee305e…

MALICIOUS

PDF

75.2 KB Created: 2021-09-21 14:20:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 2d95ae0c79ef2e95f9099e3af28bdd0a SHA-1: 3c91901c4aa7a262f9a3229a9c68496567f75cf2 SHA-256: 8b85a19143ee305e2320ec51c31fe446e1c545efabef7ceddab95a8f3bfbd207
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 CMS upload directories or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://superpart.com/files/piximisew.pdf In PDF document text
    • https://elmaga.lt/components/com_mijoshop/opencart/image/data/files/worurexigipikaruwunitadev.pdfIn PDF document text
    • http://yummyschool.com/_UploadFile/Images/file/24230067746.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/60e303f5cf2310242b2227865b3a165a/lokifimuduzalekufubipubis.pdfIn PDF document text
    • http://cyuanmei.com/userfiles/file/tizulodexilof.pdfIn PDF document text
    • https://grdr.org/paidel/ckfinder/userfiles/files/sivozojutumewubudilavi.pdfIn PDF document text
    • http://pampa.be/uploads/userfiles/files/lomuzuwugolidu.pdfIn PDF document text
    • http://gearcon-eng.com/file_media/file_image/file/merogiruzu.pdfIn PDF document text
    • http://goodlack.cz/userfiles/file/gedosomuwekaguni.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613a934cf2d3a---worizusuze.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.de/userfiles/file/37225796484.pdfIn PDF document text
    • http://dmkert.hu/files/file/46014416108.pdfIn PDF document text
    • http://ekorob.pl/userfiles/file/39834998051.pdfIn PDF document text
    • http://tieuhocsongphuong.hoaiduc.edu.vn/ckfinder/userfiles/files/70069025292.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140d1d3231a0---62536059475.pdfIn PDF document text
    • http://energo-market.ru/sadm_files/73742172699.pdfIn PDF document text
    • http://sakra.sk/storage/file/40748108044.pdfIn PDF document text
    • http://giadinhmedia.com/uploads/files/3758292513.pdfIn PDF document text
    • https://www.hotelrestaurantmacarena.fr/ckfinder/userfiles/files/22806952724.pdfIn PDF document text
    • https://flims.atelierleuthold.ch/userfiles/files/93418570639.pdfIn PDF document text
    • https://kuni.ro/app/webroot/files/userfiles/files/dotifoxexetesupexudelux.pdfIn PDF document text
    • http://horvathortho.hu/tmp/tetokazafedokujal.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/88811102710.pdfIn PDF document text
    • http://asr-net.ru/uploads/files/zusupetojedakujar.pdfIn PDF document text
    • http://e-district.org/userfiles/file/85542681719.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=harvest+moon+friends+of+mineral+town+isoPDF 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_off0000c44d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC44D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dc64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC64 10656 bytes
SHA-256: b530f94503203d3e83608c6b7d6d18d2dabd21b1d114af2d2da3748400f4e830
font_02_sfnt_off0000f4c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4C6 16320 bytes
SHA-256: 613168cca77aa692b675c21d7460d70c1dcb65aba5820cfbe8f25164137944c5