Malicious PDF — malware analysis report

Static analysis result for SHA-256 f21e949bd3f20fd9…

MALICIOUS

PDF

75.6 KB Created: 2021-05-18 11:31:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 90b1ce059fd2659d9c873ec85cf36779 SHA-1: a922b639ea7095c1f7a5df9c16760a12d9490c62 SHA-256: f21e949bd3f20fd97690ebc2474552d116bf2536963744b998569f474afc8bd2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or trojan payload. It contains multiple links to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, appears to contain search query-like text, reinforcing the lure of a search result or informational page.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609069f174d37---2828781466.pdf In PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/7409f46c3255a9ae5e0543c77d1bd333/fadokamudorutolix.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/79k5v8bsn31t0eem0uq0j1un6t/76969553355.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/asfpibhvjuth0obaaaif6dm766/16438600710.pdfIn PDF document text
    • http://amandamaitland.com/images/file/31494653683.pdfIn PDF document text
    • http://modnyi-buket.ru/uploads/files/jifuwavesetibiwamedi.pdfIn PDF document text
    • https://amerismithenterprises.com/wp-content/plugins/super-forms/uploads/php/files/89ee2a8d3e921743a2301b68b9ed86d1/sigis.pdfIn PDF document text
    • https://bistakalikotenetwork.com/userfiles/file/3311589230.pdfIn PDF document text
    • http://atonoserver.com/userfiles/file/nolofipapotabirax.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-5-10/20210510175624355829.pdfIn PDF document text
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16080a5af871d6---mimosaneweruda.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16095a1b5e6928---tosalofo.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/fdjle928dvgmc77tn7q5s6abk2/kujozakudifixolarawi.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/16091df1fb6831---jimupiwirelotisepikidup.pdfIn PDF document text
    • https://liniagdanskzydowo.pl/files/16115098589.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=what+does+blinking+blue+light+mean+on+xfinity+routerPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e79d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE79D 5708 bytes
SHA-256: 7b3407b23ef62ac7de2d72b85e528880eb8f3ef6ba8f35764dd67fd602c75248
font_01_sfnt_off0000faf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAF3 10548 bytes
SHA-256: 43daad984eb245088c519f62d9e90a9077e1de7331619a242fadb72608b38904