Malicious PDF — malware analysis report

Static analysis result for SHA-256 6fb237d068ffe661…

MALICIOUS

PDF

77.7 KB Created: 2021-09-10 13:22:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a1ffdedd44b67d8b1edd75e46fb8dc6d SHA-1: bda25abc1c620d88ca4c5158c4f22ab9cdb2bf7f SHA-256: 6fb237d068ffe6614d19200498a716b16e7793c3b5b4fab573db9781943ac6b5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are part of link farms on disposable hosting or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery via these links. The presence of embedded JS points to T1059.007, and the nature of the PDF suggests it was likely delivered as a spearphishing attachment (T1566.001).

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 7

  • 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.
  • 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://chcial.ru/uplcv?utm_term=ps5+simulator+download+android
    • http://stomerijindex.nl/images/uploads/15344672860.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/161380bb01f9f2---tijozep.pdf
    • http://proreferee.ru/uploads/ckfinder/files/suvepiwuw.pdf
    • https://iwanbim.iwan.co/userfiles/files/88091580745.pdf
    • https://g55net.com/webpagebuilder/ckfinder/userfiles/files/dovozofefojarikizorizabuv.pdf
    • https://theloneranger.tv/clients/loneranger/ckfinder/userfiles/files/550591598.pdf
    • http://25630638.kad.tw/kads/ckfinder/userfiles/files/juzufurutodozaxan.pdf
    • https://1tlstar.com/storage/uploads/files/naguboj.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/dd5fa627107be6d5887179d66efdfbb8/80770501984.pdf
    • https://castilloexterior.org/ckfinder/userfiles/files/sebanifapevam.pdf
    • https://ubitanduk.com/contents/files/80864307793.pdf
    • https://mauspro.net/upload/files/20426618329.pdf
    • http://jca-t.com/fck_image/file/37204185255.pdf
    • http://restavratorstvo.com/ckfinder/userfiles/files/vipugixewugizufumilebekuj.pdf
    • http://com123.vn/uploads/file/ferakibanufegoru.pdf
    • http://botosani.ro/img/uploads/file/busatinivopojim.pdf
    • http://deforma.it/userfiles/files/64157340708.pdf
    • http://americasbestwingspa.iorderfoods.com/uploads/files/gudimefepig.pdf
    • http://baloneacessorios.com/_upload/file///66780514102.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1612f8771009ff---39420425837.pdf
    • https://wolfgang-photography.com/userfiles/files/62217468268.pdf
    • http://paintmaster.hu/js/ckfinder/userfiles/files/71773812227.pdf
    • http://sonnenheizungen.ch/fckeditor/editor/images/file/xewimimatofiropixura.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c996.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC996 16792 bytes
font_01_sfnt_off0000e1a8.bin
ac5f7106d0d8f6a402b634d0981e684da8037df7fd37e9ff051d5ec6766f6e67
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1A8 17876 bytes
font_02_sfnt_off000110b2.bin
38d170b0700f39ab7a085c068d853fcceeebb0518f8cda62a0d9e4e9c6d205f0
pdf-font-stream PDF embedded font (sfnt) at offset 0x110B2 10600 bytes