Malicious PDF — malware analysis report

Static analysis result for SHA-256 db764280ed8f23a0…

MALICIOUS

PDF

86.0 KB Created: 2021-07-06 21:56:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: e8c46feff4f4bd26d045682e74fac912 SHA-1: 3cc0740528314a7ce84baced1184403056fd2b13 SHA-256: db764280ed8f23a0cc47cf222b2109bc0a754b71f7fea1f2ac286bcf0654319a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to malicious content or facilitate SEO spam. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/rarr3ef9cdu56ckotn19joqqut/tumenovezepikivuvosivin.pdf In PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/89f5fc311d5acc173f29ec84795b6a1f/kalarobevemigodol.pdfIn PDF document text
    • https://minhkygroup.com/luutru/files/48459111561.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/5a15f86173034367925ab2af43b17d0d/21977918445.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16087ceb5b75fa---kifewepufoposonimu.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/8r42h2td1vvd323aqv9dsa785e/4529914949.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1a2deb95f0---vukefuka.pdfIn PDF document text
    • https://k2salight.com/wp-content/plugins/super-forms/uploads/php/files/ce8beba54a3203a80ca290101dd2077d/xiwajeguterusizumawonexan.pdfIn PDF document text
    • https://amblamy.ee/upload/file/lilefivon.pdfIn PDF document text
    • http://t-p-fortune.com/userfiles/file/kunafomopa.pdfIn PDF document text
    • https://cissud.eu/uploads/ck_editor/files/mawakewuzizurarekusixas.pdfIn PDF document text
    • https://avonsteel.com/UserFiles/file/nelisogabug.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/1imgajc8f7niolk1ago3cq22me/27360000995.pdfIn PDF document text
    • https://airflow-skateboards.com/upload/file/xesokasudezokitek.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/9a3fc29c7206eaebc779a691221bea13/kotegutin.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/fb456b4309b01afadfd3f08da0b64e89/vuriwolak.pdfIn PDF document text
    • http://highendschmiede.de/highendfiles/file/42314081677.pdfIn PDF document text
    • http://ndc-group.ru/uploads/files/lomow.pdfIn PDF document text
    • http://teraval.cz/res/file/81660886177.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160943f9ab877e---85422057131.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/2qco1rqoauf0rqtj6joahc0s9t/bofavovedazenu.pdfIn PDF document text
    • http://kardelendalgicpompa.com/uploadfiles/file/21813365988.pdfIn PDF document text
    • http://waypl.pl/upload/File/bifinalivodesoz.pdfIn PDF document text
    • https://www.hemoroidklinigi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607043c2d888f---nodeselaxetozewu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=medical+referral+letter+examplePDF 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_off0000ee93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE93 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000106aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106AA 10484 bytes
SHA-256: 4e37397a8c82ccb129076273ffcc89deb81525795fe42938d2d08f735283b6d2
font_02_sfnt_off00011e76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E76 16968 bytes
SHA-256: dddc534a47e36fd498d3cff524ac670e1964427c7ec201f51b3112a34fc81bff