Malicious PDF — malware analysis report

Static analysis result for SHA-256 50f9ca4c847acb5f…

MALICIOUS

PDF

83.0 KB Created: 2021-09-06 22:07:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 9ec6f0988b6da19ead643a01ae368a8a SHA-1: b9d2208a5c533d9f46fe80ec6675c9eb7d51d6b6 SHA-256: 50f9ca4c847acb5fb8708ffbcd1aef3fdf7962714718b906827d8d5cb6db72f9
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress sites, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is unreadable, but the heuristics and URLs confirm a pattern of hosting potentially malicious files on disposable or compromised domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/16070082b22659---bebebamunutojufaman.pdf In PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085ef529413c---47424555106.pdfIn PDF document text
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/46f5aecb67adb5192b2d5775d3476b1e/49115792217.pdfIn PDF document text
    • https://thesaddlebank.com/wp-content/plugins/super-forms/uploads/php/files/lnq4glcaam6t3gq1d7jnl5req0/kujijunakaku.pdfIn PDF document text
    • https://binarbaidservices.com/public_html/userfiles/file/24218425026.pdfIn PDF document text
    • https://agermag.ro/mm/file/mirinokinebe.pdfIn PDF document text
    • http://aisef.org/uploads/userfiles/file/file/pojoxekipodomaxon.pdfIn PDF document text
    • http://vuoncotichdep.com/upload/files/nakotavolaxazuwer.pdfIn PDF document text
    • https://zlato-eu.sk/upload/files/64159769900.pdfIn PDF document text
    • http://whatdwellswithin.com/file/43296559096.pdfIn PDF document text
    • http://prabashproperties.com/ckfinder/userfiles/files/86780652852.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a260b61f1b8---sezitakuferinotipanaze.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/nfj731hvi57fr547odl1hhc7ku/norenoribovo.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/wimuxozolemeso.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/0moabf9j1va2oc8hhrpmucf679/36481592053.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/8f7480e645e18bf0d77f4ed9f3916f45/xajigetinapepujutakejoven.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16082b1326dd7e---pogibuzuvefurabirilitema.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/48f97f29bd449755a3d00aca68e7596f/pilaxubezapogufuxal.pdfIn PDF document text
    • http://innovatepc.com/userfiles/file/pefawawupurutiv.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/ieg773gppg02liqhl24dn7b0s3/53462346762.pdfIn PDF document text
    • https://harryfok.com/ckfinder/userfiles/files/35116116130.pdfIn PDF document text
    • http://laser-piskovani.cz/democms/userfiles/file/24397862505.pdfIn PDF document text
    • http://beiks.info/public/file/petiragozaxenusekumiw.pdfIn PDF document text
    • http://truhlarstvisollner.cz/data/file/91646867915.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=sustancias+que+contiene+el+tabaco+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_off0000df57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF57 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f769.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF769 18112 bytes
SHA-256: af075cf2cb34da010b8433f4952cf277a27e6bd226b135e2b073a6f24e2d2694
font_02_sfnt_off00012523.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12523 10976 bytes
SHA-256: 593f81b48259310d2a528ed0fe352de57831b982d2bfaaf2a511999aa65524c8