Malicious PDF — malware analysis report

Static analysis result for SHA-256 a990a3c1aecf97b0…

MALICIOUS

PDF

91.8 KB Created: 2021-08-19 20:46:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 02b0e1ba02ba87be561bc80027ae0171 SHA-1: 26cb532b12aa249da5090a435900cc44747396a8 SHA-256: a990a3c1aecf97b0dd77e41bb38b868700d56de364e0112af2be996402b1371b
96 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs pointing to various websites, many of which appear to be compromised CMS installations. The ML classifier strongly indicates maliciousness, and the heuristic firings suggest this PDF is designed as a link farm to distribute malicious content or phish users. No scripts were extracted, but the primary attack vector appears to be directing users to external, potentially malicious, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://coretry.ru/uplcv?utm_term=ib+business+management+paul+hoang+4th+edition+pdf PDF link annotation
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607bf2d18ace3---38389364445.pdfIn PDF document text
    • http://phongkhamthienhoa.vn/images/files/mifunowufulavixatuvuw.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/caf36444fff741c0526e27a1d5f71519/tazirirereg.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/6639ac3f8c26e48cd213bf5f41de5afd/359703257.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160eca05986f65---xuzozu.pdfIn PDF document text
    • https://alcoquimicos.com/ckfinder/userfiles/files/13752585806.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba0b0d0cf61---xanevuvotomotegumi.pdfIn PDF document text
    • https://mmszke.hu/files/file/sugiviloxeb.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091224f7af59---42659454125.pdfIn PDF document text
    • https://seerupit.dk/assens/file/kevesemivenelovunenot.pdfIn PDF document text
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/berot.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bac083eae7c---99087705766.pdfIn PDF document text
    • https://cortopolis.ar/userfiles/file/13308489399.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/0e5bf3503ccc59a8acabdba4c862fefa/22384574554.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/el9unc0dm44rbk2u5th46j8427/xopimiluwirabezapivunona.pdfIn PDF document text
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/m6m9be89e6vs2u4pvfh5l8udug/xosadijavumuzuxabiv.pdfIn PDF document text
    • http://kapelski.pl/userfiles/file/ligulifajewusobafe.pdfIn PDF document text
    • http://hong-tour.com/FileData/ckfinder/files/20210809_2F227FA0EE645AAC.pdfIn PDF document text
    • http://millecolori.it/images/file/6297144281.pdfIn PDF document text
    • http://svaz-podnikani.cz/files/file/burofurinefivomi.pdfIn PDF document text
    • http://world-green-hope.com/uploads/files/15548442099.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/c532d25c9e1fb47326165f1348076f0d/pubimukaganebig.pdfIn PDF document text
    • https://menuiserie-sainte-anne.fr/userfiles/file/vegeworo.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_off0000f6db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010ef2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EF2 11116 bytes
SHA-256: 29c2901bdc24e636102f8292de5636e25508ee8ba35e1ab5cf91b2ff5f878bdd
font_02_sfnt_off00012842.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12842 21880 bytes
SHA-256: 9faef96a03030def7f4a457f12d320eed6e7ec12c3bb6fe61b28cc453ced2ae5