Malicious PDF — malware analysis report

Static analysis result for SHA-256 fff2fe268aca3183…

MALICIOUS

PDF

73.9 KB Created: 2021-09-08 18:49:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b18c780360be3ac84dedef50bcc27b28 SHA-1: df24a7a49025fd26780ab5e1adde82f7b4e35e28 SHA-256: fff2fe268aca318306fbe06dcf0b9518a49bd681774c72c5433f5e88dad6e34e
156 Risk Score

Malware Insights

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

The file is a PDF that contains numerous embedded URLs, many of which point to potentially compromised websites or disposable hosting. Heuristics indicate it functions as a link farm, likely for SEO poisoning or phishing purposes. The ML classifier and ClamAV detection strongly suggest malicious intent, with the primary attack pattern involving directing users to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/e2mq0rg1s7fp74dmc9cb1opo92/66728610538.pdf In PDF document text
    • http://technestudio.eu/userfiles/files/72983224758.pdfIn PDF document text
    • https://edusfera.pl/upload/file/77574452858.pdfIn PDF document text
    • http://pretaporter-pegah.com/userfiles/file/89949062171.pdfIn PDF document text
    • https://elmaga.lt/components/com_mijoshop/opencart/image/data/files/21457040200.pdfIn PDF document text
    • https://www.notusweb.com.br/ckeditor/ckfinder/userfiles/files/91157561637.pdfIn PDF document text
    • https://mamap.in/ci/userfiles/files/fajesitukamu.pdfIn PDF document text
    • https://mar3ol.com/Files/files/lebukesuralodefiraw.pdfIn PDF document text
    • https://ashasuchikala.com/ckfinder/userfiles/files/vubefunumineviranutupegur.pdfIn PDF document text
    • https://pjkconstruction.ca/images/file/47104997752.pdfIn PDF document text
    • https://taptigrihnirman.com/singhania/downloads/file/67925510658.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613162a96f3dd---jexirowalupaxezesomojelaj.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/fowanazis.pdfIn PDF document text
    • http://ekorepetycje.eu/Upload/file/kerumaxizugetu.pdfIn PDF document text
    • http://happy-land.hu/editor_up/pumog.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1613897970ea72---joxogiranudirozisix.pdfIn PDF document text
    • http://clevio.biz/fckUpload/file/41570575286.pdfIn PDF document text
    • http://lonerangerfanclub.com/ckfinder/userfiles/files/taxizafaxexe.pdfIn PDF document text
    • http://www.yemany.com/yemfiles/files/jagutagivawutizadimelo.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161353f4e2d0d7---64840570631.pdfIn PDF document text
    • https://mimpishiodua.com/contents/files/75507577060.pdfIn PDF document text
    • http://ajisushionline.com/uploads/files/47897824289.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=trichomonas+gallinae+pdfPDF 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_off0000bdfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDFA 10932 bytes
SHA-256: 6f1f0fc07484d496701ecb70ff291ef8aa3aaa6454a2a715589dad97c4e2b2d1
font_01_sfnt_off0000d6e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eef2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF2 16780 bytes
SHA-256: 8c3aff30db57183c4389c8d17aa136fddaac73b0b7318b946b3c476f7c2237c5