Malicious PDF — malware analysis report

Static analysis result for SHA-256 53ff85fc6dc24b25…

MALICIOUS

PDF

83.7 KB Created: 2021-09-13 22:44:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fc696c3e2e73a373fa8bbb2fa02794ec SHA-1: d2e3b61835eac2e82c6a9b1ad8c61993b1649725 SHA-256: 53ff85fc6dc24b25478c84ea653a3f8115d36e0eab9e2f538ace788d050ac7c8
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised CMS uploads. The presence of numerous PDF links on disposable hosting further supports a malicious intent to distribute or phish.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://www.tahitotfalu.hu/ckfinder/userfiles/files/gekofukilifezojixe.pdf In PDF document text
    • http://goldenmallbiotech.com/upload/files/50863724203.pdfIn PDF document text
    • https://www.pension-chevaux-haras-gabereau.fr/ckfinder/userfiles/files/xovuwukofudi.pdfIn PDF document text
    • https://www.milestonesmn.org/ckfinder/userfiles/files/60157102985.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/xanubiv.pdfIn PDF document text
    • http://dom-2000.ru/ckfinder/userfiles/files/jerunujulubusubiwu.pdfIn PDF document text
    • http://walosports.cl/userfiles/file/3774963421.pdfIn PDF document text
    • https://qualitygums.com/userfiles/file/viragavaramezetanowij.pdfIn PDF document text
    • http://xaydunglenguyen.vn/upload/files/0dd4d4.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/19420138314.pdfIn PDF document text
    • https://webshopplus.nl/app/webroot/files/userfiles/files/ligazaz.pdfIn PDF document text
    • http://tourister.kr/userfiles/file/lotosijepoteta.pdfIn PDF document text
    • http://cpgny.com/userfiles/files/12395676839.pdfIn PDF document text
    • http://thietbikhachsanvinhhung1.com/upload/files/18592001210.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/85e19508224749ff9b34b2ddc1270bad/nitumefopikixiwagezi.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/f6b71ce6db981885abb8501e53309cfe/solosazute.pdfIn PDF document text
    • http://jfac.kr/ckfinder/userfiles/files/5590382194.pdfIn PDF document text
    • http://ccsup.co.th/uploads/ckfinder/files/4071343753.pdfIn PDF document text
    • https://aldurra.ly/images-editeur/img/file/46231050833.pdfIn PDF document text
    • https://artcorner-fiberglass.com/userfiles/files/duzapenubowejo.pdfIn PDF document text
    • http://premiercontractinginc.com/files/file/dositewujimafabuwoke.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613e5f6376087---36846905658.pdfIn PDF document text
    • https://speedwayinfo.hu/uploads/file/20451689258.pdfIn PDF document text
    • http://aftckwt.com/uploads/file/turuburebit.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=rom+ppsspp+downloadPDF 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_off0000e360.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE360 10264 bytes
SHA-256: 076e71b37b5babb6c866c826ffc7d0685cc6607b6c8b932653f94d6e52790f6e
font_01_sfnt_off0000fa79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA79 18120 bytes
SHA-256: 05d98bb9e9430fdbe7b0b42d59d3ea4dc13d978e9632e60905e16be38d52a312
font_02_sfnt_off0001295e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1295E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1