Malicious PDF — malware analysis report

Static analysis result for SHA-256 c0e857ddcf2a134c…

MALICIOUS

PDF

72.8 KB Created: 2021-09-08 07:02:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: de255813740139f503c9ee50c8fc27ef SHA-1: eaff1d8ffb368f210e6cdba2d2f77236f1a92af0 SHA-256: c0e857ddcf2a134c49d475bb9bf940b14a0986ff50e0fc625d4bad2469dd0515
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to compromised WordPress upload storage and disposable hosting sites, indicating a link farm designed to distribute malicious content. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the presence of embedded URLs and the heuristic findings suggest the document's primary purpose is to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://drafthe.ru/uplcv?utm_term=cell+membrane+and+transport+worksheet+answer+key PDF link annotation
    • http://hgbs.de/userfiles/file/2940147090.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160908ee4bbeff---kifafosariditiluxetu.pdfIn PDF document text
    • https://tp-pos.com/uploads/image/files/6381336008.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/neieefvj16vu223n6np4kbj8pu/40277690821.pdfIn PDF document text
    • http://htk2.altrodesign.eu/ckfinder/userfiles/files/zezopilumotegok.pdfIn PDF document text
    • http://easyreturn.store/userfiles/file/42836511175.pdfIn PDF document text
    • http://pscemetery.com/userfiles/file/taperutuvagixojikagulis.pdfIn PDF document text
    • http://davidhammerstein.org/userfiles/file/sudiwilirupejor.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/fdf5b45a6ebbf00b9dc6711f016bc7bc/17450341130.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1608bbc289845f---33355268928.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/290a61eddb06d7e16f8ef6e7a1c0a3dc/jesipunupagukubi.pdfIn PDF document text
    • https://thefertilizergranulators.com/d/files/58081600363.pdfIn PDF document text
    • https://unique-u.biz/images/uploads/file/vagikobapefowukuxurit.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a7e0cf8e24a---4374815549.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2c7e4430a---24149396102.pdfIn PDF document text
    • https://benqmusicworkshop.com/fupload/file/likedasoriguz.pdfIn PDF document text
    • http://sns-russia.ru/userfiles/file/63791303209.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/segexipiximivezenadukel.pdfIn PDF document text
    • http://www.clc-engineering.com/siteuploads/editorimg/file/wuralufuve.pdfIn PDF document text
    • https://protradingindia.net/userfiles/file/58300342787.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/eec908cfc6c0d57ef5eb172075836ec9/mogor.pdfIn PDF document text
    • http://nppgursaraijhansi.in/ckfinder/userfiles/files/89151575267.pdfIn PDF document text
    • https://letajicikoberce.cz/userfiles/file/54685458118.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607ad1474c77a---zironofejokikivojago.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_off0000bd21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD21 15252 bytes
SHA-256: a434e3b2a99616c2f3051757b5c166f048aee8d3e5f8f7484f7680fcc20a599d
font_01_sfnt_off0000e384.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE384 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fb9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB9B 11028 bytes
SHA-256: 0e4818eb3ba4ca2263d70759da0ee87a9ca6c5da0b577c13b922d4829f0a2797