Malicious PDF — malware analysis report

Static analysis result for SHA-256 321c3ff4282c0e99…

MALICIOUS

PDF

89.0 KB Created: 2021-06-29 11:54:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 728c0ad12a4aa1262a30ac50d29248ba SHA-1: faf5cfa8ebb808a209e686cd9b50b552fc4ffedb SHA-256: 321c3ff4282c0e9929d56bebf730b91d064f59b0f59f5c0146d959201059f8b4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting it's part of a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://queure.ru/uplcv?utm_term=how+to+link+up+wii+remotes PDF link annotation
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16092dc8292d28---guvesomudija.pdfIn PDF document text
    • http://ahs1968.com/clients/d/dc/dcea35c349c70fb55dca458fc6558ff6/File/92856261733.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1607010122f74f---4331339260.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/95632071659.pdfIn PDF document text
    • http://orchid-daikanyama.com/userfiles/file/zapufipijijawusoguvaxiku.pdfIn PDF document text
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/46845687402.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/n77f41ob55ovr21uipo3d85g86/99728812021.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607bd5b39d0c1---kelagikokazut.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a06be5321f2---59233691100.pdfIn PDF document text
    • http://kaupa.cz/userfiles/file/46356892251.pdfIn PDF document text
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/06095d2a52f4195e3903b25af20f022f/73250530174.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b736864a5f7---87691916251.pdfIn PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/37bb79b597c73473f07f3b2f4c802d3b/tojib.pdfIn PDF document text
    • http://clinivetmadonnadirosa.eu/userfiles/files/97860188013.pdfIn PDF document text
    • https://associazionedynamica.it/uploads/file/14324906036.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/otue373dsci9e5m29tmk3jj52l/pibufuragaxo.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb23c2d1af---4497454305.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080f89183f8d---73971742118.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160738a13b4a78---74904543525.pdfIn PDF document text
    • http://africanhairbraidingsalon.com/userfiles/file/23517170367.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fe54c6c14f---27504325054.pdfIn PDF document text
    • http://macautemple.com/userfiles/file/27389707478.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/5121690243.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_off0000f900.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF900 10520 bytes
SHA-256: 1b3aea7b05ea78e769b2c684f087def5ff9855f407c4407d7be112f535565893
font_01_sfnt_off000110f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012908.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12908 17364 bytes
SHA-256: f0c0385209367a9aefe83e2373d40ad7d7fcd40a210b1c445dd82891df5415d3