Malicious PDF — malware analysis report

Static analysis result for SHA-256 577a94f457516039…

MALICIOUS

PDF

85.7 KB Created: 2021-07-17 07:42:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: d3731d5d9d6b076d3d2822cd14326ebd SHA-1: 244f370e0508445e9e632a177c0fcdcec6fc9cea SHA-256: 577a94f45751603954a9c70c91f894cbf9e7b5c26ec9a7f203cdde0533e57ee5
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many pointing to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure suggests a lure to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://circolosilverblufitnessclub.eu/userfiles/files/8494772405.pdf In PDF document text
    • https://musikkursus.dk/userfiles/file/banose.pdfIn PDF document text
    • https://x-software.cz/data/file/mekoxowawozo.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd4487acf6---dopukolagew.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ccece12c1c8---solulelo.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/eacb3c874070159c9a95c6971a9cde15/rurukodeporofifezugen.pdfIn PDF document text
    • http://tokstar.com/_UploadFile/Images/file/vodosamuvoje.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/el744ocal795nruiqk9mnakto2/5341554717.pdfIn PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/a203c018b47357d46c30da9539a607f8/52444019633.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ae4b34d0aa---49664064966.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/1a86e36e45ad52eb50b51de294579e17/81332586004.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160772e86ec593---45335862686.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/c2cf328913842c6acb8e5e616bbe90dc/naladinulev.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160972bfe0c23e---metabun.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16079eb5c7f099---6147654270.pdfIn PDF document text
    • http://tano-cable.com/d/files/12917153771.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077c2b58a973---8929123647.pdfIn PDF document text
    • http://beautifulmoda.com/userfiles/files/37463986773.pdfIn PDF document text
    • http://jagodkaprzedszkole.pl/userfiles/file/21823618291.pdfIn PDF document text
    • http://konditsionery-reutov.ru/upload_picture/file/xagosowoxaretelunepepo.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/9b09948975c9ae764de1f719ffc42e19/74714097209.pdfIn PDF document text
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/406270e9c0b88b428e9f059c95d9e816/62297063688.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/8aab677269815da2d6cee89501f325ff/95080507937.pdfIn PDF document text
    • https://legacyltg.com/wp-content/plugins/super-forms/uploads/php/files/f9c89bf9be4f22e0fa642070fd4166c6/gawupi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=herb+cohen+negotiate+this+pdfPDF 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_off0000ec85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC85 10984 bytes
SHA-256: b8aacef4f0bdc0bf17b73e86095ab1214c037d62ab2f10f00ccd58032c9d43c4
font_01_sfnt_off00010582.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10582 16776 bytes
SHA-256: b50d109e94ad28f321d60b77e8548cf1a8e54dd3dac52d410d43e95091ce3cfb
font_02_sfnt_off00013149.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13149 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1