Malicious PDF — malware analysis report

Static analysis result for SHA-256 4859a7c912facef8…

MALICIOUS

PDF

74.5 KB Created: 2021-09-12 04:02:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: bdba7db85962a942dbaed0010ce48a5e SHA-1: 4362b3fae1d10061e13bc205ee9884329854ab4b SHA-256: 4859a7c912facef82ef6584c60df2b8c6e7307897c9fa7552c9c9a96ec3d144e
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was identified as malicious by an ML classifier. It functions as a link farm, containing numerous external URIs pointing to websites hosted on compromised CMS platforms. These links are likely intended to lure users to malicious sites for phishing or to download further malware. The use of compromised upload storage and disposable hosting suggests an attempt to obscure the true origin and destination of the malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • 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 https://smidgel.ru/uplcv?utm_term=android+10+talkback PDF link annotation
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/85hrmpm444odb6cb8p2jkkjp70/78786383223.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/33edf77969edb26a14ee5ed658b6db52/57615826115.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/dd6aca10bc82f347fdaf2b6fcd6a5461/dutixaruvezubuvuva.pdfIn PDF document text
    • http://dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/lutolepisujakunaxi.pdfIn PDF document text
    • https://kingbakerypans.com/userfiles/file/32484744633.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/13859676183.pdfIn PDF document text
    • https://www.fishhabitatnetwork.com.au/application/third_party/ckfinder/userfiles/files/74724606629.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1613d2524b8725---93518084414.pdfIn PDF document text
    • https://hatinhjobs.com/upload/files/93166117192.pdfIn PDF document text
    • http://woykoff.hu/upload/file/vupopawus.pdfIn PDF document text
    • https://camelcarpet.org/d/files/59739932713.pdfIn PDF document text
    • http://euroambulans.pl/userfiles/file/75224174252.pdfIn PDF document text
    • http://vitrine-prof.com/files/18314535374.pdfIn PDF document text
    • http://kirakuramenandsushi.com/uploads/files/zapevoniwesege.pdfIn PDF document text
    • http://erbamedica.org/userfiles/files/11157462331.pdfIn PDF document text
    • http://franklcalabreseattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/95598564128.pdfIn PDF document text
    • http://santamariamikado.com/uploads/files/kivutovopaxazu.pdfIn PDF document text
    • https://istocdukkan.com/userfiles/files/jatupaponidus.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/161364d159e55a---88065218610.pdfIn PDF document text
    • http://arkystudio.eu/userfiles/files/tupimilizinidumupeze.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/4b2da701f4eb69e8380ac6bf1ca3a89e/gutosubojilologeda.pdfIn PDF document text
    • http://studiopedrazzini.eu/userfiles/files/ferimaroxivavemativas.pdfIn PDF document text
    • http://dongzzang.com/userfiles/file///titefu.pdfIn PDF document text
    • https://tenekedjieva.com/uploads/file/8423060414.pdfIn PDF document text
    • http://watch62.ru/files/files/zekuze.pdfIn PDF document text
    • 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_off0000bfd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFD3 17112 bytes
SHA-256: 33e39241a789389a1829ba929bc3561ae1aa7fe89775452e03a1bd7ec679c502
font_01_sfnt_off0000ebc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBC6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103DD 10452 bytes
SHA-256: 47cc9266bbeba0e0ac332c9e2604d9baab162d500cdb35ea88a228ec19f2f378