Malicious PDF — malware analysis report

Static analysis result for SHA-256 6e53f875c4ce98b7…

MALICIOUS

PDF

79.9 KB Created: 2021-08-16 20:48:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 843ceb3971e64bb71387fd769ae28949 SHA-1: 923b02cc8f518987eafb96adc48c2045b245a840 SHA-256: 6e53f875c4ce98b70670395059b1285ce6cdedc4671fe0670eb94c3ab4704e5a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting it functions as a link farm to distribute further malicious content or phish for information. The presence of external URIs and link farms strongly suggests an attack pattern involving directing users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://lncxjzxxw.com/upload_fck/file/2021-5-22/20210522155318196408.pdf In PDF document text
    • https://caffedisanto.it/file/14344817743.pdfIn PDF document text
    • https://www.harasportcenter.com/wp-content/plugins/super-forms/uploads/php/files/s4vk1u6e8ar9d71aesa8rp8l26/tonekipegimusubuxugi.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/6839244105.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/varofiluwigenunifuwejeb.pdfIn PDF document text
    • https://lawweb.info/mycms/admin/userfiles/file/noxulomuxaxipotamatog.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/c4pjcpa08ki5d8mckeabqe6feq/63472157034.pdfIn PDF document text
    • http://popnmusic.fr/userfiles/file/51721479142.pdfIn PDF document text
    • https://nolimitscenter.be/peausitive/images/FCKeditor/file/wiroliwajutot.pdfIn PDF document text
    • http://cwesp.biz/upload/file/zuxego.pdfIn PDF document text
    • https://rockyshairsalon.com/wp-content/plugins/super-forms/uploads/php/files/e7p92b3pqbr4j5irlssa2snv5k/sabidonurok.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/8d46d8c1cc4d6b9457a12153aeff5537/28896062034.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bcff3631166---pixunabuvukarulos.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/d7k8vfn8i0pb56npp0ftdo3m9e/54838520225.pdfIn PDF document text
    • http://vncanada.vn/uploads/files/98263716719.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///78550338717.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/tnbm8teb3cr0lu9mncao37g0s8/jofepakopubuzak.pdfIn PDF document text
    • http://hilltop1976.com/clients/24685/File/vonozejesunovaberimid.pdfIn PDF document text
    • http://nordicaluminium.ru/userfiles/file/71879623076.pdfIn PDF document text
    • https://derfo.info/resimler/files/dibakebiduwezinabegodupej.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=1+metro+cubico+cuantos+metros+cuadrados+sonPDF 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_off0000d098.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD098 10680 bytes
SHA-256: ef43e62a5fd5d63d596ec30c4023a6e09bf7cea7d00edc332b57f4fdac2d0ae9
font_01_sfnt_off0000e90d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE90D 18584 bytes
SHA-256: 42357d594c4cf862c80236511818c72e9bace4f597f383a81d826b568fa68038
font_02_sfnt_off00011879.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11879 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1