Malicious PDF — malware analysis report

Static analysis result for SHA-256 ffb5cbad2bec5391…

MALICIOUS

PDF

76.1 KB Created: 2021-09-27 04:56:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 459e1b5836beaced2e22b802dea036dc SHA-1: 09e4604be0bcd756776c2b847042f99ac6d0b615 SHA-256: ffb5cbad2bec53914e5e68579a4aba1e792df9cfd3d2b01fd4f491de160bd178
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. While no scripts were explicitly extracted, the PDF structure and link farm behavior suggest an attempt to redirect users to malicious or phishing sites, potentially for credential harvesting or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1613e1bf69ceb9---vijurejipanavobojizijapif.pdf In PDF document text
    • http://utuin.net/files/fckeditor/file/13466644699.pdfIn PDF document text
    • https://anfauglir.com/images/file/wefeweduposizexagosiloju.pdfIn PDF document text
    • http://atputasbazes.lv/images/userfiles/files/44567919584.pdfIn PDF document text
    • http://lovec.bg/root/ckfinder/userfiles/files/boxoniwodagopugerosa.pdfIn PDF document text
    • http://paulabenveniste.com/UserFiles/file/zasenezufizozewegi.pdfIn PDF document text
    • https://thic.net/plugin/ce1/ckfinder/userfiles/files/tunabuluxoxagawibo.pdfIn PDF document text
    • http://kondicionery-domodedovo.ru/upload_picture/file/nuxejezesug.pdfIn PDF document text
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/wojebejaforufibifa.pdfIn PDF document text
    • https://ispartaorganizasyon.com/ckfinder/upload/files/30162591279.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/2f7p4o7rfkp61fn2fgqf4jl482/vorapusojaki.pdfIn PDF document text
    • http://gearcon-eng.com/file_media/file_image/file/dabozikekogevofeluzonovex.pdfIn PDF document text
    • http://agenturamotivace.cz/uploadfiles/file/20926998800.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/161500bb1e8b08---pewogixakogamituxobomak.pdfIn PDF document text
    • http://www.slenderclub.cz/ckfinder/userfiles/files/wugivu.pdfIn PDF document text
    • https://cornerstonelaw.eu/userfiles/file/bijubetave.pdfIn PDF document text
    • http://problemconsulting.com/img/download/files/pineripul.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/09/03/file/38486008006.pdfIn PDF document text
    • https://kudamatsu.org/userfiles/file/mowipuwil.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/161371f1e7e954---10615187200.pdfIn PDF document text
    • http://rc-saty.cz/gais/image/file/8765118782.pdfIn PDF document text
    • http://specialcats.nl/media/files/lelofutevanifogajifus.pdfIn PDF document text
    • https://fibra-optica.ro/ckfinder/userfiles/files/63300884624.pdfIn PDF document text
    • http://satakantaresort.com/user_img/files/girosuvigojutajufudozi.pdfIn PDF document text
    • https://ventadeterrenosurbanos.com/userfiles/file/powanakofisalezozikomo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=geometry+honors+textbook+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_off0000bd4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD4E 10952 bytes
SHA-256: 6403bbe3b34026239c3b86656b635d299805de995c54f5ed595ca4503f4a0e1f
font_01_sfnt_off0000d65d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD65D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE6F 20360 bytes
SHA-256: 2a456fd798488dff16497b635f50af0b39bb8611644cbfbb1d7f1c587982fe40