Malicious PDF — malware analysis report

Static analysis result for SHA-256 441eb58b6121598b…

MALICIOUS

PDF

68.9 KB Created: 2021-09-28 18:59:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: adb0e1c165885e36853a52a9d7d2465f SHA-1: a8b9e4309eb49cae68866e3f2f43306b7560ac4c SHA-256: 441eb58b6121598b27de2edb4df9c8cfac890ce5a966e757bd1b010f9bff7ed3
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to potentially compromised websites or disposable hosting. The presence of numerous unknown URLs suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://cgemfoco.com.br/ckfinder/userfiles/files/xekupixarulutuxakava.pdf In PDF document text
    • http://kamkmori.cz/ckfinder/userfiles/files/67081520526.pdfIn PDF document text
    • http://shiokuda1.com/contents/files/butikilijuwanoguzitam.pdfIn PDF document text
    • http://mobilahomedesign.com/userfiles/files/92092840205.pdfIn PDF document text
    • http://faw-asia.com/image/upload/files/33014840968.pdfIn PDF document text
    • https://dreamscapes.ca/dream_scapes/userfiles/files/67138980861.pdfIn PDF document text
    • https://privatecambodiatour.com/userfiles/file/jexufodezajoxisesovulafof.pdfIn PDF document text
    • http://autoklej.pl/app/webroot/media/files/jukarur.pdfIn PDF document text
    • http://toshiteriyakiburien.com/uploads/files/suxoxifuli.pdfIn PDF document text
    • https://ngonluathan.vn/images/ckeditor/files/nujepaz.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/161459a618ee1c---77761528392.pdfIn PDF document text
    • http://centralcogtc.com/uploads/file/kajozoromipadewunalasi.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/fdcb39834bb72929af0f82b4b2be0a15/gutizo.pdfIn PDF document text
    • http://ambcavallon.eu/userfiles/files/44623305688.pdfIn PDF document text
    • http://limuzine.md/userfiles/file/xanifofelolumiwusapag.pdfIn PDF document text
    • https://isosklo.cz/uploads/bixedefekudi.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/86753373901.pdfIn PDF document text
    • https://www.esicm-old.org/admin/lib/ckfinder/userfiles/files/wixojumademorega.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161403f550762b---68175550268.pdfIn PDF document text
    • http://videotour24.com/data/fckupload/file/88263823106.pdfIn PDF document text
    • http://deliver.cueicha.com/assets/upload/files/86978826258.pdfIn PDF document text
    • https://divinescience.in/userfiles/file/vafivevexiwogimubuteritam.pdfIn PDF document text
    • https://hongdung.vn/ckeditor/images/files/62793757802.pdfIn PDF document text
    • https://markaoyun.com/calisma2/files/uploads/88487579354.pdfIn PDF document text
    • http://k9careclinic.in/ckeditor/ckfinder/userfiles/files/24060326044.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=free+memoji+androidPDF 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_off0000b09f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB09F 15344 bytes
SHA-256: b83df3f4b069299189d46478f6bb502c20f2ccacc0b6d9a700dfeaf1e2936136
font_01_sfnt_off0000d74c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD74C 10204 bytes
SHA-256: 967bf247b96959006acad37e7702c8a376c500aff6b84a249aa3b39fdfdad3f3
font_02_sfnt_off0000ee01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE01 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1