Malicious PDF — malware analysis report

Static analysis result for SHA-256 d2c8e9bfb44644ef…

MALICIOUS

PDF

84.4 KB Created: 2021-10-06 10:29:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 55ceba9aedcfd70300c69afab6ad9532 SHA-1: 2233c24f96843c93292250f6f7715ea15e193e99 SHA-256: d2c8e9bfb44644ef15a6ca3b10ef5c673a608a8cd69dcb044c206570bbb9f12a
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with several pointing to compromised CMS upload directories, indicating a likely phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is unreadable, but the heuristics and URLs confirm a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://sumisaedu.com/FileData/ckfinder/files/20210927_D93DF503D7E57A05.pdf In PDF document text
    • https://idea-web.ro/app/webroot/files/userfiles/files/9726702415.pdfIn PDF document text
    • http://surmounttravel.com/userfiles/files/98802946604.pdfIn PDF document text
    • https://calienglish.com/ckfinder/images_store/files/1432642168.pdfIn PDF document text
    • http://catwalkexotique.com/userfiles/kabizariletugawatupuzu.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161300086579db---mefikozirivagewedotati.pdfIn PDF document text
    • https://bwhe.in/ckfinder/userfiles/files/tipalaluxerogotokux.pdfIn PDF document text
    • https://bomnuocebara.com/quangbasanpham/app/webroot/upload/image/files/kepunafodobodopapet.pdfIn PDF document text
    • http://wojno-stal.pl/pliki/file/lirikonowiguli.pdfIn PDF document text
    • https://zegaoyun.com/calisma2/files/uploads/kiridetawiwir.pdfIn PDF document text
    • http://kcwoman.medsoft.kr/pds/userfiles/files/98200463389.pdfIn PDF document text
    • http://jjw-led.com/userfiles/file/79110320491.pdfIn PDF document text
    • http://nuovojob.com/userfiles/files/73234557887.pdfIn PDF document text
    • http://eamenfaraz.com/cache/fck_files/file/61810711347.pdfIn PDF document text
    • http://newtarrytowndeli.com/uploads/files/31776451034.pdfIn PDF document text
    • https://rendszergazda-cegeknek.hu/ckfinder/userfiles/files/xuzutudimukibegug.pdfIn PDF document text
    • http://larrysiegellaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vowumitu.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/b14c6ec11a322c00e4c84b4d2dca5d72/bugamemurak.pdfIn PDF document text
    • https://ehlibeytalimleri.com/resimler/files/tegaruka.pdfIn PDF document text
    • http://otvorene-srdce.sk/userfiles/file/jidawovibuveladered.pdfIn PDF document text
    • http://kmjjt.com/uploadfiles/file/010403485048.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ae3b3b38a1---jofexamozexolofobogobemug.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/niwipixal.pdfIn PDF document text
    • http://bolt.fo/public_html/userfiles/files/lipasizor.pdfIn PDF document text
    • http://dallard.fr/ressource/site-image/files/87090766171.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=party+nominees+are+to+primaries+as+the+president+is+to+thePDF 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_off0000e18a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE18A 10728 bytes
SHA-256: 0e8445e54a6763c5065007938c01d738cd931230b2c9b564154915c34db862b3
font_01_sfnt_off0000fa00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA00 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011212.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11212 18956 bytes
SHA-256: a5c755887a7e77fe516e4010120f0fac091b6a8aae9e98274b0e16e0706bed11