Malicious PDF — malware analysis report

Static analysis result for SHA-256 e11666d4ef7214f5…

MALICIOUS

PDF

81.2 KB Created: 2021-09-03 07:49:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 2a4505c3c516b4674b73d1027dfe0f28 SHA-1: 731efee6f3464d5f730a7ef8389e33d65628375e SHA-256: e11666d4ef7214f5382bdbc7b58dbfe8444966760131963b736332682a1e534b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious destinations. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users to external sites.

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 https://crewmak.ru/uplcv?utm_term=convert+pdf+to+coreldraw+format+online PDF link annotation
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e0d7799e143---5212929573.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/1bc4303776d05c4dc30e897f70500842/wedaf.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609742562affd---49422445467.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1aba2ed135---fidikefizoz.pdfIn PDF document text
    • https://fotobolfestmeny.hu/mvc/userfiles/file/lolagozikeme.pdfIn PDF document text
    • http://186086.com/upload/files/rogeranapofewonagevaro.pdfIn PDF document text
    • http://jfe.hk/userfiles/wukalafakasok.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/u5khfnea884kd7hpl70peqs0r0/ritis.pdfIn PDF document text
    • http://hokeypokeychallenge.com/clients/7/77/77ac66e313b6cb4bf602f1678accca72/File/217429037.pdfIn PDF document text
    • http://evrofurnitura.by/elax-furnitura.ru/uploads/files/todiwaba.pdfIn PDF document text
    • http://vandervalk.reviews/app/webroot/files/userfiles/files/25409220630.pdfIn PDF document text
    • http://www.premiumimport.nl/ckfinder/userfiles/files/24285958425.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///3757324757.pdfIn PDF document text
    • https://prosaison.fr/userfiles/files/35350930577.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1938a02c3d---xabizemaxukabomeluzis.pdfIn PDF document text
    • https://giant-nano.com/app/webroot/userfiles/files/61037319290.pdfIn PDF document text
    • http://naosgym.com/userfiles/files/velapobexi.pdfIn PDF document text
    • http://olympicburger1988.com/uploads/files/fevigi.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fa866f5beb5---musunuwepubep.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/rvodf8vhlg9omfp2fscrq1os4k/sonemiwabe.pdfIn PDF document text
    • http://hyeminshop.com/DATA/files/pubegivolozojozageta.pdfIn PDF document text
    • https://tatsolarlight.com/uploads/files/35657356173.pdfIn PDF document text
    • http://mebelhotel.ru/userfiles/files/sulosefagipom.pdfIn PDF document text
    • http://shamayachts.com/upload/file/88124301735.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_off0000d849.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD849 17544 bytes
SHA-256: f510db0e7096871cedac01cdeed57f8291e788c3386c33d96fbb4ea38cd8035a
font_01_sfnt_off000105b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B6 10796 bytes
SHA-256: 262ff329b8a3bd00750f1a617648a1bf5134e43eacc761b9ef954d7cd9c77390
font_02_sfnt_off00011eab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EAB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1