Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b5b5c1d10930ea6…

MALICIOUS

PDF

93.8 KB Created: 2021-06-28 07:11:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 31896957bd36ba97d8179af86d637fcf SHA-1: 95337faa7ef646e87be81a99ca856d992d27710d SHA-256: 3b5b5c1d10930ea63740933a7fe691fc16a5acaad609286c635b3a556b29e73c
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to numerous URLs hosted on compromised CMS uploads and disposable domains. These links likely lead to phishing content or further malware, aligning with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://asijskepotraviny.cz/files/file/gujisalenanugoxika.pdf In PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160904ec922bad---nobifebenovowo.pdfIn PDF document text
    • https://takeorders.online/wp-content/plugins/super-forms/uploads/php/files/b105ef36j4ujmsh2hhhpvc3jsa/14354668727.pdfIn PDF document text
    • https://cualuoihoanmy.com/uploads/userfiles/file/42659663159.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160925434b3772---fepipiwi.pdfIn PDF document text
    • http://shipsupply.ru/userfiles/files/rujam.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb42a476908---66555263129.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a748de9f938---48045752072.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/160753685dcf10---xezepuxewabovexeju.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/9aea3c9eb3cb326f52e72136b852ad09/jixojojelinejudipominof.pdfIn PDF document text
    • http://kxnjl.com/userfiles/files/jatavoj.pdfIn PDF document text
    • http://sjar-tech.com/uploadfile/file///2021052218141448.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b54d9e4d63d---4092458247.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/ju364e7j5uutsu8ekeec5aaaf1/jiwejagemekumiworudusupaz.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/takixozuwufi.pdfIn PDF document text
    • http://nuraski.pl/wsg/userfiles/rumidejefabagalerawe.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/84813372682.pdfIn PDF document text
    • https://fajanav.com/aym_image/files/26645181757.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16071a9b976b8f---32106342136.pdfIn PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/96330393225.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/heu4rjd1d05l2ge4cstd5dk4aq/sazolotuwusosuron.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/817809f315338eb551978b2d82c93303/nozefawoperusugid.pdfIn PDF document text
    • http://aeronautike.com/userfiles/file/kifuwibujufebuxixegojiju.pdfIn PDF document text
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/3424ff6b8cfecb3e6769661cd976f42c/mumetasimit.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdac4ce92b6---90667927534.pdfIn PDF document text
    • http://billedbutikken.dk/articlefiles/file/nufafevasudimogavevokof.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=geography+grade+12+bookletPDF 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_off0001076f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1076F 19156 bytes
SHA-256: 3c600a2ca47afa07ef3ec4bf0ebb06282ad9f3fde1b918389ee57940c7a4f97b
font_01_sfnt_off000138c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000150db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x150DB 10864 bytes
SHA-256: 37cf8d5507989a0228495eb17269e6c8d27049e2bcbc5917de7e3193c7d97da3