Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d5184c58e7a543d…

MALICIOUS

PDF

84.1 KB Created: 2021-09-17 11:51:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 39497e1b303f277fb299572a48559224 SHA-1: b33098dd5c93c4352661d260755ede3d3967d52d SHA-256: 6d5184c58e7a543dc2d9225c59dee54838ecd108bd77a551981549805f677672
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, indicating a likely phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly support its malicious nature. The document body is heavily obfuscated and unreadable, providing no direct user-facing content, but the heuristics clearly identify the malicious intent via link farms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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 http://kolkandkolkdesign.com/site/data/ws/files/notegasogexofonabeme.pdf In PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/a2od08appeuvc3gc7o205r8gq5/51344967278.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16136b417760cc---13847824411.pdfIn PDF document text
    • http://kliknetezde.cz/admin/obrazky/file/vagisowalumi.pdfIn PDF document text
    • https://norservis.com/files/files/mamebu.pdfIn PDF document text
    • http://atel-j.nl/uploads/files/14302922998.pdfIn PDF document text
    • http://stefani.cz/fck/file/piforetewegazilafi.pdfIn PDF document text
    • http://birizgardenhotel.com/userfiles/file/4585000343.pdfIn PDF document text
    • http://rintoyo.com/userfiles/file/lugif.pdfIn PDF document text
    • http://happyorderfood.com/uploads/files/82516763672.pdfIn PDF document text
    • https://zakarpattya-tour.com/upload/wokopanenakeje.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/77981811890.pdfIn PDF document text
    • http://thuocamakong.net/userfiles/image/file/566014604.pdfIn PDF document text
    • http://gardatrans.com/content/Files/81838792042.pdfIn PDF document text
    • https://camphacement.vn/upload/files/dedosifenunagigodipijexu.pdfIn PDF document text
    • https://www.passion-rnd.com/upfile/files/2021/09/14/wojunawer.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/d4c8c61e009c088f0da874b845715286/kufugulifezuxafem.pdfIn PDF document text
    • https://lazdynumokykla.lt/userfiles/file/budodowudugawadopug.pdfIn PDF document text
    • http://xn--c1aejbdnke.xn--p1ai/admin/ckfinder/userfiles/files/wubefavijepolaganiz.pdfIn PDF document text
    • https://fabriziochessa.it/userfiles/file/30695587103.pdfIn PDF document text
    • https://dom4m.com/userfiles/files/gufefose.pdfIn PDF document text
    • http://cattaneoarchitetti.it/userfiles/files/2521034293.pdfIn PDF document text
    • http://etpatatietpatata.com/userfiles/files/80069333510.pdfIn PDF document text
    • http://dkkarsin.pl/img/upload/files/feret.pdfIn PDF document text
    • https://galaxy-training.com/userfiles/file/24822853206.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=best+free+games+on+iphone+2021PDF link annotation
    • http://louisiana-arts.org.s150269.gridserver.com/siteuploads/editorimg/file/tixujod.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_off0000e3a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3A1 11104 bytes
SHA-256: 3e78e4e492a915165b6e9a8fab0bfe447bf7c7b05d1e788c7a724d65cd945000
font_01_sfnt_off0000fd76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD76 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011588.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11588 17392 bytes
SHA-256: a43d27e6d138eca60072fa9c2ccc3fc3183744a43f3d31ceeea3b6efc8d806a3