Malicious PDF — malware analysis report

Static analysis result for SHA-256 850a68cd30683456…

MALICIOUS

PDF

85.5 KB Created: 2021-09-07 00:38:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 7be5bc6822d2cf44b9a9caab0f52ec8b SHA-1: 480d544ac63bbc5e5f1899ef97ec183cf4d61b57 SHA-256: 850a68cd30683456ecba363c4234664c1637f69b5f145d60fbbaf0b3309e106f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains embedded JavaScript, which is a common technique for executing malicious code within PDFs. Additionally, it features a link farm pointing to multiple external PDF files hosted on various domains, some of which are identified as compromised WordPress upload storage, suggesting an attempt to distribute further malicious content or conduct phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://barrierball.cl/ckfinder/userfiles/files/funovolirizozexikapebix.pdf In PDF document text
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608115a77f675---66002753529.pdfIn PDF document text
    • https://dptech.vn/uploads/files/55235820049.pdfIn PDF document text
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/a457e657b379c7bb57c67af12a005227/83311118331.pdfIn PDF document text
    • http://lhs60to70.com/clients/3/32/32806278e47d7e4d905c37b1d6ebf04a/File/najipeve.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/laxudejela.pdfIn PDF document text
    • http://xn----dtbhwhggdaoqfh3d.xn--p1ai/media/file/37173729015.pdfIn PDF document text
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/1608b533548890---vaxefivev.pdfIn PDF document text
    • https://baileyelectrical.services/wp-content/plugins/super-forms/uploads/php/files/m38e16qhjn01lqmblt9h34btgr/lupumojukusigejonubujiki.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607db7021191a---mixit.pdfIn PDF document text
    • http://stark-tools.ru/images/uploaded/mofasetulakokimaduvure.pdfIn PDF document text
    • https://www.algeos.com/js/ckfinder/userfiles/files/27231093551.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612e443448ab6---70094581932.pdfIn PDF document text
    • http://ttworld.hu/uploads/content_files/files/83194612696.pdfIn PDF document text
    • http://rford67613.com/clients/a/a2/a20594cba7d6fe247bc87ef9b80620db/File/wopogiwegofik.pdfIn PDF document text
    • http://technology-mp.it/userfiles/files/levixifepafikamisodasit.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083685d09e92---fuluwogupizasula.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/160f7cd0601b44---dutakubiwejomuvatedugoba.pdfIn PDF document text
    • http://cityhelps.org/clients/6/61/61afa7a028a8e04f14432b0fece6f2b0/File/tonukifilududuno.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160979ccc9c9aa---zuzoxojajagefu.pdfIn PDF document text
    • http://moscow-vernisage.com/files/files/dawokizogi.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/53066abadbb2371ce86b30715c79f7d8/55175682513.pdfIn PDF document text
    • http://cjatkinson.com/userimages/12408802299.pdfIn PDF document text
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ed6400fbff---77117123108.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=extrusion+press+maintenance+manual+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_off0000e8bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000100d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100D1 17144 bytes
SHA-256: 3066ea02f21ecc41e8981bb556892ad429197089ed60b78ddb1ef2946ad58855
font_02_sfnt_off00012cec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CEC 10964 bytes
SHA-256: f1feee5cce05dd90ab24b72f5603578c7bc5922cc24af265cb21fe8764ef4e56