Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ca04cddd90e0d39…

MALICIOUS

PDF

86.1 KB Created: 2021-08-26 04:24:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0f0bfed2245a216846df1785d92105a9 SHA-1: d288e808c2546bbbbf9cfafd2af12ff636eea3ae SHA-256: 5ca04cddd90e0d397297a8d082b99b52624806d90551791a6c0b5d7a47e7d3af
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS upload directories. The ML classifier strongly indicates maliciousness, and the structure suggests a link farm designed to distribute malicious PDFs or manipulate search engine results. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://jandenzobv.com/image_uploads/file/xagakinadarafux.pdf In PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bdc0fc21ce2---62954831648.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16083cf64df720---wewejonisomal.pdfIn PDF document text
    • http://www.pranabkumar.com/fckimages/file/ziwugiwapiliboxep.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/cpprkmcot4sngmmfg5ndalf0k1/75142006822.pdfIn PDF document text
    • https://granitnet.hu/editor_up/93809722373.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/jinj4mh19ld3o17ggm83h4ceh5/4531796842.pdfIn PDF document text
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/831b0a8848ae0420a8e87a1b3d72517b/tefaluvo.pdfIn PDF document text
    • http://spostojow.pl/userfiles/file/59421956605.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/0d5826cf8abf820e3bd2d70e4854c297/67962390000.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b47cee61470---foxodibifu.pdfIn PDF document text
    • http://schokozentrale.de/idata/37096876631.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/b1ec07eef3d778bbe4da622b8aeff24f/jolizilumi.pdfIn PDF document text
    • http://sibmetiz.ru/upload_picture/18830048034.pdfIn PDF document text
    • http://myrbacken.se/login/ckfinder/userfiles/files/punetituxaguvo.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160be1d93397bf---72961669880.pdfIn PDF document text
    • http://belean.pl/userfiles/file/gimukijunopo.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/202fc685ff14d594d4ba978a5a54e1fc/manedetidogafudisilawow.pdfIn PDF document text
    • http://allmedicus.com/userfiles/file/vejuvesojibumamumabez.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608572d3edc1e---tadeguredoguke.pdfIn PDF document text
    • https://gamaconsultores.cl/upload/file/tabatanos.pdfIn PDF document text
    • http://webinaris.org/ckfinder/userfiles/publics/files/21919492501.pdfIn PDF document text
    • http://bephoangdung.vn/uploads/ckfinder/files/77800839294.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=christmas+tree+sketch+imagesPDF 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_off0000ec2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC2B 10532 bytes
SHA-256: d76ddd8ee2fd3bcea1a18904bb8921c12ceef5a1c0b147f3e79b266e3224bbad
font_01_sfnt_off00010439.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10439 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011c4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C4B 17192 bytes
SHA-256: 2d67a0e23c25b9be2acc0b0cde56b8fb01e73b8b1ea8d69452687efae2ed367e