Malicious PDF — malware analysis report

Static analysis result for SHA-256 c819ab73bc86179d…

MALICIOUS

PDF

80.5 KB Created: 2021-09-21 05:54:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 916a73bf8a7ddbfc98597c5a948c80ae SHA-1: fbb4a9c5584acba1c3424d2b3419cddac9f83f3e SHA-256: c819ab73bc86179d2e7fd8f66ba230cfa764d5551c908ed7e30217ac3f77d4b0
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm or SEO poisoning tactic. The ML classifier strongly indicates maliciousness. While no scripts were extracted, the nature of the URLs and the heuristic firings point towards a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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=wobbly+life+download+free+android PDF link annotation
    • http://sictombbi.fr/ckfinder/userfiles/files/68503812272.pdfIn PDF document text
    • http://toitureetfacade.fr/data/Files/49005394373.pdfIn PDF document text
    • http://stainless-faucet.com/uploads/htmlupload/files/dixonowizavobo.pdfIn PDF document text
    • http://chpcentre.com/files/file/zafuwabafa.pdfIn PDF document text
    • http://armanetti.com/images/vabevijotofasulibativoda.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/ov4d46ckuq46cnt129hmu5foi7/79542495145.pdfIn PDF document text
    • https://afmiletisim.afmiletisimajansi.info/resimler/files/jazuxuludowozim.pdfIn PDF document text
    • https://uangraja.com/contents/files/2550559265.pdfIn PDF document text
    • https://nacituran.com/userfiles/file/boranagewomavejopu.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/87109ea2cc46c36f019475a6751409d3/73903165283.pdfIn PDF document text
    • https://mtmhomeschool4art.com/mycms/uploadedimages/editorUploadedImages/file/34994589806.pdfIn PDF document text
    • http://prodottoitalia.eu/userfiles/files/gosewokenawemo.pdfIn PDF document text
    • http://letnipohar.cz/upload/file/dokuguriwozumowabaxosukan.pdfIn PDF document text
    • http://stauarchitetti.eu/userfiles/files/towakutanin.pdfIn PDF document text
    • http://www.memoriahistoricamalaga.org/ckfinder/userfiles/files/viburivikulajotivus.pdfIn PDF document text
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/44221778038.pdfIn PDF document text
    • https://avphunter.ro/ckfinder/userfiles/files/tunefazivavigobi.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/161392b11abf27---zozolumalogovexixi.pdfIn PDF document text
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/167d890257a9c399425ca0cc0d95e95b/8344247178.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/16148c9b4b9ead---98409488370.pdfIn PDF document text
    • http://jedwines.com/cmsCart/upload/file/sizasiwejiwurokebifi.pdfIn PDF document text
    • http://vivatbacchus.hu/files/file/lizokofefozajom.pdfIn PDF document text
    • http://gpe-el.pro/ckfinder/userfiles/files/67080264477.pdfIn PDF document text
    • http://megatex-plast.ru/pub/file/gegosuwazuwupusab.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_off0000d7f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f00b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF00B 10412 bytes
SHA-256: 113a0354e88652bb1245f8e5d76f93b975ff985f9bde5f53035f4a0d39b3fd81
font_02_sfnt_off000107be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107BE 16848 bytes
SHA-256: 698af57d422fa6758ad28246614462fb323ada6b19bf097020b46d18dfe05a8a