Malicious PDF — malware analysis report

Static analysis result for SHA-256 56e43a65b387cb63…

MALICIOUS

PDF

80.1 KB Created: 2021-09-03 18:01:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 15f2fb8ced8ca22a822563a8c3b88049 SHA-1: 371e4daa90d43d9bf965ed82469a319e2bfd1da5 SHA-256: 56e43a65b387cb633a32da89fbbb48639015b4c8f98088934b79176b9531d92d
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm or phishing lure. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for human readability but rather to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • 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.
  • 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://nonbodepsg.com/uploads/files/39676368742.pdf
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/2196adf231f2a281b17f747a02e66af2/33862844723.pdf
    • http://nhasachconggiao.com/luutru/files/kutabusep.pdf
    • https://9ja-bet.com/userfiles/file/4627190285.pdf
    • https://desertflying.club/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3f9fd9715---2045799727.pdf
    • https://ventadeterrenosurbanos.com/userfiles/file/38083725574.pdf
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/e8d794840e8de4b5de9814fe97cfa569/32912020643.pdf
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/dd49436ea6bd3ca8296099ed46b6e4a4/20406984613.pdf
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d78050aac1---4264611834.pdf
    • http://www.yankey.com.tw/demo/public/editor/ckfinder/upload/user_upload/files/75343826593.pdf
    • http://isspskola.lv/userfiles/files/kilusizuwixowupu.pdf
    • http://dynamicyunnan.com/ckfinder/userfiles/files/bolewi.pdf
    • http://alhouti.com/userfiles/file/41552141372.pdf
    • https://kme.pl/global/app/webroot/uploads/file/16231762872497.pdf
    • https://marosme.ro/hirek/file/mexaw.pdf
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160767efe7c3f6---98749605821.pdf
    • https://sunnyrosesschool.com/userfiles/file/90641428389.pdf
    • https://clicksnepal.grnca.org/img/files/files/lisonevunijeroxelepoxot.pdf
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609b87648467f---zinufadexil.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/fcffd16769eb313c8c8cbdb1b5b5192b/sinemuwal.pdf
    • https://allmassage.net/upload/file/20210801111122.pdf
    • http://noithatachau.vn/webroot/img/files/mobovarudiv.pdf
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c62094c4e02---92345090429.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/mdt58ochm156ack1k9qjt08rv6/nomefujuxamufujuraza.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/fd5935198574131ff21969cc6e8b02d5/51009055128.pdf
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607183df34b11---tegowudogojovamexoxur.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=cn7510a2001+honeywell+valve+actuator+manual
    • 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_off0000d233.bin
59b1949af818eccba682be486875a906cc2f4fb747e2360ea7d8ff61a5b9289e
pdf-font-stream PDF embedded font (sfnt) at offset 0xD233 17936 bytes
font_01_sfnt_off00010023.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10023 16792 bytes
font_02_sfnt_off0001183a.bin
6fdd89aee04687b9df35b7b2c2ce6cff267e3a5b23e9d1d18957b9910eb74437
pdf-font-stream PDF embedded font (sfnt) at offset 0x1183A 11112 bytes