Malicious PDF — malware analysis report

Static analysis result for SHA-256 1171967e9e6144f4…

MALICIOUS

PDF

80.9 KB Created: 2021-09-10 17:50:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 433b72d2ed6584d873b4b3715ec822db SHA-1: 918f806e164ffcfeae83eb827b77dc62bb6025e8 SHA-256: 1171967e9e6144f4b2286d1ff74887ab4397c3a15d202e2774546ccb1faa89b9
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to domains that appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the link farm itself.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://daeryuhealthcare.com/ckupload/files/bijelevixejoliseluf.pdf
    • https://www.sesc-am.com.br/Selecao/ckfinder/files/42524323523.pdf
    • http://rotarytattoomachine.co/project-new/christianbook/upload_images/file/ruriratikujomeju.pdf
    • https://solturism.ro/images/file/32049310565.pdf
    • http://www.americaninvest.net/upls/files/24196557660.pdf
    • http://daimarconstrucciones.com/images/admin/file/85704957074.pdf
    • http://tuivaivietnam.com/uploads/files/luxutigamexijelakan.pdf
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/afe1be0912b7d87307c983afd75d04f5/77208450077.pdf
    • http://hzqljsj.com/images/upload/File/99988234731.pdf
    • http://auto-rad.pl/userfiles/file/xasoxoxadubo.pdf
    • https://wyslijpaczki.pl/app/webroot/files/userfiles/file/fegizobexezenezew.pdf
    • http://foto-recepty.sk/images/fotky/58688255131.pdf
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/002be80af35d1a37142d5521c24d0a1f/87080253772.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/161367eb89e6ba---natukomiriz.pdf
    • http://shopgraeagle.com/ckeditor/uploads/files/luforinifewe.pdf
    • http://asu78.ru/userfiles/file/fawigimo.pdf
    • http://garant-fond.ru/ckeditor/ckfinder/userfiles/Images/files/zaseruzunosevurikubedelel.pdf
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16136b68e0eed3---fegowobutakawisupidu.pdf
    • http://tavaszitura.eu/userfiles/files/35921630321.pdf
    • https://rails-bg.com/fckeditorfiles/file/71755804473.pdf
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612f25ba6ac16---54427648120.pdf
    • http://merlegdoktor.hu/tmp/20468014980.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=el+dia+que+se+perdio+el+amor+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d33c.bin
90d4edcd841295776e4ed6a41e1718a7bd120a1b34263cdb8dd0a5a826592b7c
pdf-font-stream PDF embedded font (sfnt) at offset 0xD33C 19540 bytes
font_01_sfnt_off0001057e.bin
696604125bda4bc7866c69be47af5ccbc4d4e65dce2ad0f436fae0c0b7a3be14
pdf-font-stream PDF embedded font (sfnt) at offset 0x1057E 10688 bytes
font_02_sfnt_off00011db9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11DB9 16792 bytes