Malicious PDF — malware analysis report

Static analysis result for SHA-256 637d05fae409107e…

MALICIOUS

PDF

87.2 KB Created: 2021-09-01 05:27:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 4c9e01bcf0e124b83eb2f2e12a001e7b SHA-1: e7b58cec8b1fe9c1c9249fb279cece2f337a37f9 SHA-256: 637d05fae409107e7d851ae5c6bb36926bf184db2284dbfeda20ca64ef1aba62
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses an urgency-based lure. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://philabc.ru/uplcv?utm_term=branch+accounting+questions+and+answers+pdf PDF link annotation
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/79a1d8e5c8874ad50d6b523f7389bb1b/66971801822.pdfIn PDF document text
    • http://www.arborvitae.cz/ckfinder/userfiles/files/fowiwotosupuwozubabikana.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/e72fc55b6e804559cd65841aee9e1ced/64590568459.pdfIn PDF document text
    • http://www.logistiekverbeteren.nl/ckfinder/userfiles/files/lomali.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/88815c17fcfff78613357a8542c6da35/buramotipagurifuko.pdfIn PDF document text
    • http://alnadaoil.com/userfiles/file/83017546780.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1610d379a2c5f2---luwufezuwotowixa.pdfIn PDF document text
    • http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160772570639f3---puximezaveda.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/4von5ljiiigqa2c8k1v8k550r0/23622236132.pdfIn PDF document text
    • http://kondicionery-dzerzhinskij.ru/upload_picture/file/wotodedorebafanowe.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160807e0270218---2151550296.pdfIn PDF document text
    • http://seritour.com/rsm/files/zenetobub.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160cff989a8801---92659320169.pdfIn PDF document text
    • http://parkhigh65.com/clients/4970/File/xenegowozefedidemomudiner.pdfIn PDF document text
    • https://www.justgym.co.za/wp-content/plugins/super-forms/uploads/php/files/buhp2s1h9v3u2vksq97gis2h6o/43536735817.pdfIn PDF document text
    • http://aceonlinementors.com/userfiles/file/febebawaso.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/160984a85da4a4---bonoxipikitudu.pdfIn PDF document text
    • https://sbmhavacilik.com/userfiles/file/68028439106.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/giwavagu.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cc4a1564bf3---6529136741.pdfIn PDF document text
    • http://digjamaica.com/app/webroot/files/89918483086.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d543f2f1945---vabirerefifar.pdfIn PDF document text
    • https://area34.info/wp-content/plugins/super-forms/uploads/php/files/pu7lfsqgi6sm5111uv396t6md5/seguxil.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607950de13a88---66813054766.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_off0000ee26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE26 17872 bytes
SHA-256: ffa9ada062ce64f873a04fb3bd0da7d857e9836c821eb15445db0f8541a88752
font_01_sfnt_off00011cd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CD7 11240 bytes
SHA-256: 218e917b9ea81452edf9751a744390e727170bbd9208a3217982e3ab46057517
font_02_sfnt_off000136bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1