Malicious PDF — malware analysis report

Static analysis result for SHA-256 753898284193f539…

MALICIOUS

PDF

69.9 KB Created: 2021-09-23 07:52:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: dc331f5460a8ed575a39a6579237d5f1 SHA-1: a37cecd62c221f5209b990e5908b6076128dd860 SHA-256: 753898284193f539fe6fba23e0d1f3d79593ef8c434a395cde3c9fd609234305
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains multiple heuristics indicating it functions as a link farm, directing users to various external websites. Several of these URLs point to compromised CMS upload directories or use disposable hosting, suggesting a malicious intent to distribute or host malicious content. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 5

  • 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://dwallacelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tuvamezufagaloka.pdf In PDF document text
    • http://www.companyforte.com/imagenes/editor/file/wevunubedixajerabipobed.pdfIn PDF document text
    • http://mamtomchabahai.com/uploads/files/files/23614684223.pdfIn PDF document text
    • https://www.seblocation.com/ckfinder/userfiles/files/78293365202.pdfIn PDF document text
    • http://enotecagaribaldi.it/userfiles/files/48452200910.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/09/02/file/wonerixedabas.pdfIn PDF document text
    • http://constantcontinuity.com/membership/data/files/38351572653.pdfIn PDF document text
    • http://phuongdonggolf.vn/app/webroot/uploads/files/pidawazowibofok.pdfIn PDF document text
    • https://cuatudongsaigon.net/uploads/files/watukenejosulilufajov.pdfIn PDF document text
    • https://adikmanis.com/contents/files/pexijopogawuwuzavitupifem.pdfIn PDF document text
    • https://bczenekar.hu/files/file/pademamosegebaf.pdfIn PDF document text
    • https://bawaniint.com/ckfinder/userfiles/files/11728502407.pdfIn PDF document text
    • http://phutungquanghieu.com/app/webroot/files/ckfinder/files/zumuk.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613453c222e61---wagolu.pdfIn PDF document text
    • https://minhgianggroup.vn/upload/files/65923193780.pdfIn PDF document text
    • http://cravaluos.com/ckfinder/userfiles/files/19104026746.pdfIn PDF document text
    • https://fokusmedia.com/images/uploads/89454905377.pdfIn PDF document text
    • https://sieuviet.net/webroot/img/files/kibavewoxuwofomano.pdfIn PDF document text
    • https://kermanrooz.com/img/files/dozane.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144e6aa5c733---63634208155.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/49d898525b56b379949bd172426f58cc/jigewodosinigarifo.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613769a5dc3a0---gigupedubelefagimuna.pdfIn PDF document text
    • http://99hospitalitygroup.com/ckfinder/userfiles/files/11852125598.pdfIn PDF document text
    • https://webmanagement.colortown.ro/images/file/19594703547.pdfIn PDF document text
    • https://eledigitalpr.it/allegati/file/38779579930.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=rapidex+german+speaking+course+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_off0000b125.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB125 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c937.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC937 15276 bytes
SHA-256: dad703507c50dfa8d0f9be872c62afdfc916b1d00a772a7c7085d87c836a7e97
font_02_sfnt_off0000efea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFEA 11156 bytes
SHA-256: 92c2785038144ec37f2e64cce8e441ed613d79010e7d018f5a765ff446aeeb12