Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8fd22a47c3d7c2f…

MALICIOUS

PDF

77.7 KB Created: 2021-09-19 17:06:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c7e1d18cb3db5f851a9db811c5bce6c1 SHA-1: 785f9f59b81c4a5cbf22a5f82f6215fee514c621 SHA-256: d8fd22a47c3d7c2f9fb4e4d60686da55c6df54a2655f79f46f56111e3d742fed
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised websites or disposable hosting, indicating a link farm designed to lure users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond what the heuristics reveal.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://endeligmandag.no/e-brev/data/div/92131676455.pdf In PDF document text
    • http://gibisch.com/files/files/24921486621.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16132f3d57fb16---99769998371.pdfIn PDF document text
    • http://iseveranscopy.com/upload/editor/file/29525797242.pdfIn PDF document text
    • http://hyunshin.net/userfiles/file/87267863587.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614659dfe999a---33496641375.pdfIn PDF document text
    • http://ruresept.ru/files/file/68622965347.pdfIn PDF document text
    • http://thanhnhomdinhhinh.net/uploads/files/wotokizopufaxig.pdfIn PDF document text
    • https://actaviaserica.org/board/file/files/59886423927.pdfIn PDF document text
    • http://synergytaekwondo.com/click2buy_newp/userfiles/file/mibobirejevisumiridoditez.pdfIn PDF document text
    • https://healthlantern.com/ckeditor/ckfinder/userfiles/files/xijomujalibukav.pdfIn PDF document text
    • https://nutstudio.it/userfiles/file/57476349394.pdfIn PDF document text
    • https://rpdev.org/ckfinder/userfiles/files/91451561942.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/a3996cb464ea63d50da643302ea51a37/wubedire.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613519a423ddd---14298347262.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/fizavixivowubitevezotabok.pdfIn PDF document text
    • http://svatba-emi.com/uploads/pages/files/45483368650.pdfIn PDF document text
    • http://cartopack.be/Images/file/tivakekago.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/62272320224.pdfIn PDF document text
    • http://paliukenas.lt/i/File/13547238393.pdfIn PDF document text
    • http://zensushidanapoint.com/uploads/files/57842323425.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/am40ibs1nvn79rhi0pg29cqkf7/xuzojoralivebu.pdfIn PDF document text
    • http://www.mustwalge.ee/data/content/files/19702884513.pdfIn PDF document text
    • http://avandcie-automation.com/ckfinder/userfiles/files/48912047438.pdfIn PDF document text
    • http://solee56.com/ckfinder/userfiles/files/gafopojodolepekoduxomo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=best+game+downloader+appPDF 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_off0000cbfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBFC 10784 bytes
SHA-256: 79e158bd18b882e172a0dc9924bd272cce5cc1620a8e23aad47e80969b90cc0a
font_01_sfnt_off0000e4b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4B4 17192 bytes
SHA-256: c02e33750368c49e57c80efb96e5e4e5549ff3569c170fbac259bf8851259f33
font_02_sfnt_off000110bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1