Malicious PDF — malware analysis report

Static analysis result for SHA-256 9838b870d1232f32…

MALICIOUS

PDF

87.1 KB Created: 2021-09-09 09:37:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f17dba4f31a19998eb5dd171c1072006 SHA-1: 616b0dff4522b9a80105a626abb309db01f33dbe SHA-256: 9838b870d1232f32b7904f4ff862f7db53233095c004324aa087645fba5fe937
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the presence of a link farm and the ML detection suggest the document is designed to redirect users to malicious sites, potentially for further exploitation or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.esicm-old.org/admin/lib/ckfinder/userfiles/files/10083126907.pdf In PDF document text
    • https://festival-bg.com/media/ckuploads/files/vejaruzupuxir.pdfIn PDF document text
    • http://www.coverseg.com/uploads/ckfinder/files/zivuvilumovugojuxemuxad.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/rotezasitogud.pdfIn PDF document text
    • http://promocode.lu/userfiles/files/19413145690.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/161309e7745a60---2277177545.pdfIn PDF document text
    • https://ratoempat.com/contents/files/zodudarazukanisotazogoju.pdfIn PDF document text
    • http://donghobaoan.com/uploads/files/wemapitinivozakegok.pdfIn PDF document text
    • http://frappsreagent.com/upload/files/39396488990.pdfIn PDF document text
    • https://gs-hemeringen.de/ablage/userfiles/files/235071589.pdfIn PDF document text
    • http://metabolit.ru/files/file/zogaberovojamusoka.pdfIn PDF document text
    • http://playeasypiano.com/resources/fck_images/mofusivaxuzozuwetuxa.pdfIn PDF document text
    • http://www.badischer-kunstverein.de/ckfinder/userfiles/files/85056962577.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613896dfb09c5---foluxenitimolunixabu.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/96899180975.pdfIn PDF document text
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/61925b48606d721a54a166e5bb1cfc88/83021023899.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130a7df37615---78519823369.pdfIn PDF document text
    • http://erbaytag.com/resimler/files/49671063077.pdfIn PDF document text
    • http://poliinc.com/upload/files/60125799544.pdfIn PDF document text
    • https://ist-lb1.istanajp.com/contents/files/9402617306.pdfIn PDF document text
    • http://wangyiphk.com/userfiles/wukudetotuzule.pdfIn PDF document text
    • http://cnsgawefgl.netsociality.com/upload/files/78335295132.pdfIn PDF document text
    • https://deltarealestate-eg.com/userfiles/file/ratikifoja.pdfIn PDF document text
    • http://productinfo.in/konadnew/userfiles/file/70212709766.pdfIn PDF document text
    • https://galerie-louise.be/userfiles/files/sadipiviwipevaxeseri.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=iptv+smarter+firestickPDF 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_off0000f1e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1E4 10480 bytes
SHA-256: 007bfd321685d3a177207fc4a38883e4ac012a4fa152ee75741db84b6a08fe7c
font_01_sfnt_off000109d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109D1 17300 bytes
SHA-256: 13c91fece482b072b90ef55243797128feb25adf524c7ae6e3d65b8cdafd4b73
font_02_sfnt_off000136ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1