Malicious PDF — malware analysis report

Static analysis result for SHA-256 20bc85ed831dc52b…

MALICIOUS

PDF

76.5 KB Created: 2021-07-03 21:49:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 942e5656ea9cb3db87ef86924ceb3a78 SHA-1: 8f558ce8a27eb756cd3f5da5c3a0b0d2ef89e550 SHA-256: 20bc85ed831dc52bb86c1755590887f2e238bff4e76f6ac21d2ccf9e30018670
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links pointing to various domains, many of which are hosted on compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 https://coretry.ru/uplcv?utm_term=5+gallons+is+equal+to+how+many+quarts PDF link annotation
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/e9b896904f84da8becc4601cc78ba365/61951445964.pdfIn PDF document text
    • https://bibliotheque-des-arts.com/ckfinder/userfiles/files/48220826446.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/eoj0ib8e491g5u3d1unjn4g3f0/sopazojabemanave.pdfIn PDF document text
    • https://thucphamtruongxanh.com/Upload/files/finitivolisetof.pdfIn PDF document text
    • https://www.beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/124b74748032fb8d7b2b4ab8690c0c43/bunuwa.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce4dc0628e2---xezezumabebetuximozazobeb.pdfIn PDF document text
    • https://maychieuvinh.vn/upload/files/vuxolusanajodimulorazaluv.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/snsja8oi4oqccaeqvvenrg32ub/jiwowetafejonujeritodi.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2ece1a0c03---gowafotale.pdfIn PDF document text
    • http://loveperfectionschool.com/upload/file/wisupo.pdfIn PDF document text
    • https://oteaexpert.fr/cite_imgs/file/vefod.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606eea4d51cdd---78591021214.pdfIn PDF document text
    • https://djennebeads.com/nbloom/fckuploads/file/pedoluvelaraxivumid.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/17c81c5d5e1bccb024f84a3b664ee23f/pemavixesupiniwefov.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082119285bb3---kojiwabaferusavibipiwux.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/dobogavim.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1608b72c51cdfa---69122327574.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/mcdifnaibkogi4n00eef5ajie0/99986509027.pdfIn PDF document text
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/2e6c565fe666b9c54720619581e9c0cb/82338161767.pdfIn PDF document text
    • https://elesud.it/img_pagine/file/93356653497.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16099fd9eb9111---lukusabufelevilikige.pdfIn PDF document text
    • https://toananhmedical.com/uploads/files/kisaxu.pdfIn PDF document text
    • https://gamma-electronics-eg.com/userfiles/files/53944702221.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c470f2c31bc---depigizumab.pdfIn PDF document text
    • 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_off0000c7bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7BB 11036 bytes
SHA-256: 19d93c10433b0d7684268ac8f90b8726c1e7057a141bd1a928fdc9f42c4593f7
font_01_sfnt_off0000e101.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE101 16684 bytes
SHA-256: 0668ded976d2d784b6a8c62d11ce4ef6ce2ad8b19703b70eb571085d5f0ab674
font_02_sfnt_off00010c8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1