Malicious PDF — malware analysis report

Static analysis result for SHA-256 6bca803460c4fca2…

MALICIOUS

PDF

82.0 KB Created: 2021-08-29 12:00:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bee170d8f62161903e9f32711097e96c SHA-1: 50feec788822cdfa123d241228492f58c054402c SHA-256: 6bca803460c4fca20156ec53158f9a99ac00cd551fb5534394f2cb9cc752bdd0
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious content or manipulate search engine results. The ML classifier strongly indicated maliciousness. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://artenika.pl/fck/file/90466610546.pdf In PDF document text
    • https://paklya.su/design/img/upload/file/55936982374.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/50905953b3c4fe5e4c8717823e9ac028/58605833013.pdfIn PDF document text
    • https://ovalpolycoats.com/media/44773119348.pdfIn PDF document text
    • http://avandcie-automation.fr/ckfinder/userfiles/files/relamumikakiwatovimunis.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609abd0a6d8b1---76131629272.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/6113bc787b1191501a5a03b4c929883a/90577109059.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609cf5a1120af---72695411972.pdfIn PDF document text
    • http://stark-tools.ru/images/uploaded/70283474976.pdfIn PDF document text
    • http://kunjipsc.com/uploads/files/wazinew.pdfIn PDF document text
    • https://uniqrelation.com/userfiles/file/tudoj.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/v53hdjdbinkcohvdn5fq2s3lh7/33560857933.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/160801eaa649b2---13098708577.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7c83e874a4---netalez.pdfIn PDF document text
    • http://probeg2000.ru/files/userfiles/files/nedabogu.pdfIn PDF document text
    • https://extremedriveline.com/ckfinder/userfiles/files/331971634.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611c37d3aee02---87159031728.pdfIn PDF document text
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/ed4488178f1eda7062dc9bff5a9ca3b8/26779565104.pdfIn PDF document text
    • http://cyc.cz/pictures/clanky/files/78251183401.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160919ad825444---48352471074.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16077aa4fcc260---zitevumonibefoxizof.pdfIn PDF document text
    • http://lt101shop.com/userfiles/files/pubadupexatibitopav.pdfIn PDF document text
    • https://abandassociates.com/ckfinder/userfiles/files/vuguladuvesax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=sharp+pain+in+right+side+of+neckPDF 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_off0000db56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB56 11020 bytes
SHA-256: 0803468da5ed2cc7ebff758e56ed1151ac6d1cdbcbbcb9f7a747ea5f0b2b65a3
font_01_sfnt_off0000f4b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B6 17108 bytes
SHA-256: 945dabc071ebfa9a3578e3413dcced4c2fe1d18a07230039db65906f4fe6f087
font_02_sfnt_off00012120.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12120 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1