Malicious PDF — malware analysis report

Static analysis result for SHA-256 c51c966d06a79416…

MALICIOUS

PDF

68.5 KB Created: 2021-09-13 20:20:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 1707a712aa9fb29032d80f4991d7356c SHA-1: 69503cd072d934bce65468772cede7fc0ee7c772 SHA-256: c51c966d06a794164879788024a583ac22c006f71dda7eb8a51942cac470d8ec
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF exhibits characteristics of a phishing lure, including an image-only appearance and embedded links designed to redirect users to external sites. Heuristics indicate it's a link farm on disposable hosting, likely intended to host further malicious content or redirect to phishing pages. The ML classifier and ClamAV detection strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://basumati.com/app/webroot/ckfinder/userfiles/files/dovitarolerejowofofu.pdf In PDF document text
    • http://mpu-beratung-brendle.de/userfiles/file/41414308929.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16139caac93a55---muwoliniguxi.pdfIn PDF document text
    • http://www.sm.ac.th/ckfinder/userfiles/files/voxaxaragupavogowetubi.pdfIn PDF document text
    • https://doxity.ro/ckfinder/userfiles/files/dedifunipejom.pdfIn PDF document text
    • http://mebelhotel.ru/userfiles/files/12252602383.pdfIn PDF document text
    • https://digireg.ru/upload/27514109684.pdfIn PDF document text
    • http://hurtmar.pl/Upload/file/37386653959.pdfIn PDF document text
    • https://dreamscapes.ca/dream_scapes/userfiles/files/pemulojurew.pdfIn PDF document text
    • http://ellissi.org/userfiles/files/dikerawomotilorebo.pdfIn PDF document text
    • https://legend-chang.com/UserFiles/files/jevasovusagedi.pdfIn PDF document text
    • https://njshore.drinkpoint.com/uploads/files/98251298860.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/2a5ac7fc6275b901009ee7b7c1b12cd3/25289259514.pdfIn PDF document text
    • https://cheeselicious.net/UserFiles/file/katapu.pdfIn PDF document text
    • https://natatourism.com/userfiles/files/vemogadogivamadonasulibu.pdfIn PDF document text
    • http://inoxbienhoa.com/upload/files/37069439677.pdfIn PDF document text
    • http://goldmustang.com/files/files/pikedakubeto.pdfIn PDF document text
    • https://5of7edwardstreet.com/assets/media/files/33585785928.pdfIn PDF document text
    • http://avandcie-energy.fr/ckfinder/userfiles/files/xitajesitamuwise.pdfIn PDF document text
    • http://melvin.cz/data/konabad.pdfIn PDF document text
    • http://www.szphotar.com/admin/img/files/nebesifazovaxedumu.pdfIn PDF document text
    • https://lolakarimova.uz/ckfinder/userfiles/files/finedigukujopemanuf.pdfIn PDF document text
    • http://struttur-arch.it/userfiles/files/95209219241.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1613c185a51e40---30546603931.pdfIn PDF document text
    • http://hotechike.com/files/files/dojomasapupanofetak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=telegram+cannot+send+video+messagePDF 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_off0000b072.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB072 14328 bytes
SHA-256: 681734f576f8c5eca3f38d9166059cd883b94c234a7e0de5ec6f08ff3fe6c607
font_01_sfnt_off0000d395.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD395 10740 bytes
SHA-256: 639f50c839a61553ce4504299029a69b65975a94569170fe1836d1c2ec2b607b
font_02_sfnt_off0000ec1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC1A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1