Malicious PDF — malware analysis report

Static analysis result for SHA-256 686a82a85eb5d3f8…

MALICIOUS

PDF

87.7 KB Created: 2021-07-18 06:49:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: a8f4c8a64839de661f920e6dd6b9be5c SHA-1: 307dc37ec83f668b76507c612696f908cb0e70da SHA-256: 686a82a85eb5d3f8461080e420431bd05b478a7af29667496d600d11863507b5
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised CMS upload directories. The document body is unreadable, but the presence of numerous external links, including one to a compromised WordPress site, suggests a phishing or malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • 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.
  • 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 http://acupunctuuryao.nl/ckfinder/userfiles/files/damilupuzebimojurika.pdf In PDF document text
    • http://alnoorcity.com/userfiles/file/61277182651.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607faed65bb0c---pitekisoxevotoneluzofufim.pdfIn PDF document text
    • http://eltonltd.ru/sites/default/files/uploads/99230057394.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa316240f7---99770851981.pdfIn PDF document text
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c163ef02ef0---fiwiverimavovavalewosez.pdfIn PDF document text
    • https://vieclamday.com/userfiles/file/finosonuwiniwobas.pdfIn PDF document text
    • http://nedirajtebosnu.net/userfiles/file/vuxanap.pdfIn PDF document text
    • https://szabobuszrendeles.hu/files/files/44040948098.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/63d7e74d8fa1c0a5589afc88e7b2c6d2/lulopoxodebepewewobip.pdfIn PDF document text
    • http://arcomproltd.com/userfiles/file/difadodavi.pdfIn PDF document text
    • http://soft-pro.hr/upload/datoteke/dokafuxajisorup.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/kovelibelepizoxonedajogul.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609622670cc0e---wunevized.pdfIn PDF document text
    • http://daotaonhaccong.com/uploads/userfiles/file/xolijidux.pdfIn PDF document text
    • http://aeronautike.com/userfiles/file/wurowolef.pdfIn PDF document text
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607879f4465c9---vevifopele.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/cc5d009548c27c4251e05a4c95f6bd60/10663296331.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fca81c5e03---64668969257.pdfIn PDF document text
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/vnknqc61bp6imvcbgifdb352a7/mozezazoz.pdfIn PDF document text
    • http://www.melloecastro.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609070b2237da---pobobonawolepujosupepe.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/3d65321f1e1a3764ee541840890cb7df/dazukawunajewukena.pdfIn PDF document text
    • http://erdivigado.hu/userkepek/file/38425031270.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c616681b89f63dc9100ea71e0d3297ba/75420823372.pdfIn PDF document text
    • http://fecoil.com/userfiles/file/94539230554.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=2020+shelby+gt500+super+snake+for+salePDF 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_off0000ef95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF95 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000107a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107A7 17936 bytes
SHA-256: 90fe05a3c79add61110313459a93d282e64fa350d0020921db1c30302e257ff6
font_02_sfnt_off00013703.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13703 11268 bytes
SHA-256: 0ad12a5df15e73a5bf2345f527f15c525e7ecb2207039a353b94561396505a10