Malicious PDF — malware analysis report

Static analysis result for SHA-256 541dcdf7586e9903…

MALICIOUS

PDF

82.1 KB Created: 2021-09-05 14:52:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 13ccd753b001d8a83398adeb5f144f5a SHA-1: bc23e6e73860fc158cf6bb24fe091527b87d2d43 SHA-256: 541dcdf7586e990326a069fb399de0b959c35a32d1ffe79c709737027fb74579
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It functions as a link farm, containing numerous embedded URLs pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting. The primary purpose seems to be directing users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://wastran.ru/uplcv?utm_term=ctet+sanskrit+syllabus+2019+pdf PDF link annotation
    • http://hak-al.com/resimler/files/53525616743.pdfIn PDF document text
    • http://info56.ru/userfiles/file/fivix.pdfIn PDF document text
    • https://www.kindspring.org/inc/ckfinder/userfiles/files/mibubijazidiwigifolini.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f756643108---9652096894.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a48c86c1ff---tavuxonaxel.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/16112a590c7ee4---27785102304.pdfIn PDF document text
    • https://www.ppmcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/cb247kf1ha2farrrl20gokvg3q/kojefan.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16124e3b749347---56282309538.pdfIn PDF document text
    • https://amrapalispot.com/userfiles/file/75613855496.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2359fb83e8---57485211519.pdfIn PDF document text
    • http://screen.by/images/file/mabodeworowuvidivutavu.pdfIn PDF document text
    • http://naturallabs.de/userfiles/file/69018184012.pdfIn PDF document text
    • http://airholic.com/UpFiles/WebEditorFiles/file/65973553967.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/f930006eec9be6d19d12ac24e4349960/27219862422.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a65b4b83b68---fizimurafepa.pdfIn PDF document text
    • https://iringmalaysia.com/ckfinder/userfiles/files/49812384877.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-5-1/20210501070321602542.pdfIn PDF document text
    • http://www.vikingmaterials.com/img/mubexon.pdfIn PDF document text
    • https://air-separation-supplier.com/d/files/wubepavovujagulofe.pdfIn PDF document text
    • https://www.alarisusallc.com/wp-content/plugins/super-forms/uploads/php/files/dfc582eb69409177416b9f4c73045eec/6528207589.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/b51pmohu7eop1g0pvlqqmvghb6/tipomuvosuvamomu.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/c5b19e96e95578057bfefcc37e67c42c/pemaz.pdfIn PDF document text
    • https://gofropack.com/wp-content/plugins/super-forms/uploads/php/files/c73a4afeae4e113bf2020e2f5436b9a1/2427624673.pdfIn PDF document text
    • http://heyumpnd.com/userfiles/file///48051906781.pdfIn PDF document text
    • http://charlotteellisscholarship.com/clients/a/a5/a56794a54ce3a7e2a8fdc514f00cf952/File/vulenuletejexa.pdfIn PDF document text
    • http://intergeored.com/upload/File/visimixijezo.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_off0000d308.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD308 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB1F 11312 bytes
SHA-256: 45f4391e9c72c83b2b9789e452276b0ffa1608ef386a5b3768544f7dc064763b
font_02_sfnt_off000105c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105C2 19632 bytes
SHA-256: 50b054e2c1b01e56131eb75afcb5da7e336860200bfb992a8316a7b914aa001e