Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6815c3a7a8a1996…

MALICIOUS

PDF

93.4 KB Created: 2021-09-21 00:00:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f75500f85516af10a47b08403643d211 SHA-1: 3ec1b0bfe36d9ee0baccf2efc33254b55e8cf1d7 SHA-256: f6815c3a7a8a19962f6f2933b62ebb883423a840a7e067ef436f97b94f23d6ab
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various domains, including compromised WordPress sites and disposable hosting. This pattern is commonly used to distribute phishing content or redirect users to malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9899

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://ketchas.ru/uplcv?utm_term=laboratory+manual+in+physical+geology+12th+edition+answer+key+pdf PDF link annotation
    • https://losungversorger.com/product/file/50254813658.pdfIn PDF document text
    • https://mytalk7.com/_UploadFile/Images/file/27999072578.pdfIn PDF document text
    • https://ptkas.com/kingkong/userfiles/files/34887906234.pdfIn PDF document text
    • http://epwuae.com/userfiles/file/ruziniputuz.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/68075c5fd3a9b3f1b7f26a845dff2ee9/wizejebexixe.pdfIn PDF document text
    • http://handinks.com/ckfinder/images_store/files/zudilasefunu.pdfIn PDF document text
    • http://color-gateway.com/userfiles/file/zikulovopobaboxipejij.pdfIn PDF document text
    • http://pasaru.com/upload/files/xumepotevivafagujamazo.pdfIn PDF document text
    • http://yanartekstil.com/firma/files/fewedu.pdfIn PDF document text
    • https://futurefacesmiami.com/uploads/file/susaloko.pdfIn PDF document text
    • http://kdekdyjak.cz/data/36434518439.pdfIn PDF document text
    • https://webmenuplus.com/images/file/97000513075.pdfIn PDF document text
    • http://ambvetfanini.eu/userfiles/files/pepusopiroxumenukasogoxu.pdfIn PDF document text
    • http://sjanzee.nl/file/61735259478.pdfIn PDF document text
    • http://esteticka-stomatologie.cz/files/content/file/88415297404.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614211a0a96ab---34336123819.pdfIn PDF document text
    • http://fmafirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/52256265397.pdfIn PDF document text
    • http://www.fashiongale.ro/userfiles/files/gawajimudopubalolas.pdfIn PDF document text
    • http://arisutour.com/ckupload/files/51229595878.pdfIn PDF document text
    • https://www.sherpachristain.org.np/ckfinder/userfiles/files/gowojigomefalemiwibirozer.pdfIn PDF document text
    • http://zkmeiqi.com/admin/ckfinder/upfile/files/xofotolozile.pdfIn PDF document text
    • https://alcc.c-zentrix.com/ALCC/mail_attachments/multitenant-ws-01/1/1630976392.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613538b806118---wijumezifalefun.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e46747505e---41816915510.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/11113870099.pdfIn PDF document text
    • http://xy-interior.com/uploads/files/202109170557132306.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_off00010491.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10491 11728 bytes
SHA-256: d9ba9b6e169318f3050c5bd9b860c2af0a34478636ead636ce519d55e6563453
font_01_sfnt_off00012022.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12022 18052 bytes
SHA-256: 06182bdf997e7b03f613a39a5417cff608f68569b5bd65ce513d583b9bb04b68
font_02_sfnt_off00014f05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14F05 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1