Malicious PDF — malware analysis report

Static analysis result for SHA-256 b92902cf29388da9…

MALICIOUS

PDF

78.1 KB Created: 2021-09-20 01:16:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: dcb4e433d100f19dc9adbe607a362f4f SHA-1: 1945b15098f637f5bf82d89dab09aa799bc3df71 SHA-256: b92902cf29388da9fce63aec0135643aae8637da8f56c05283705002b75c97a7
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier strongly indicated maliciousness. The primary purpose appears to be a link farm, likely for SEO manipulation or to distribute further malicious content, rather than a direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://seteo-dechets.com/images/file/jebozezakunefibunawilem.pdf In PDF document text
    • https://clifestyle.net/uploades/userfiles/file/14520457440.pdfIn PDF document text
    • http://yksskj.com/ckfinder/userfiles/files/93822400599.pdfIn PDF document text
    • http://www.predia.cz/userfiles/file/kanasalame.pdfIn PDF document text
    • https://777mto.org/contents/files/dasokajizipejuko.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e3904b824---1420395280.pdfIn PDF document text
    • http://mansiya.com/uploadfile/files/jemidopezefe.pdfIn PDF document text
    • http://davidhammerstein.org/ckfinder/userfiles/files/wevokurozemi.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4077f417c---34345606434.pdfIn PDF document text
    • https://maximatrimony.com/ckfinder/userfiles/files/wukibomuvogun.pdfIn PDF document text
    • https://camelcarpet.org/d/files/29859390386.pdfIn PDF document text
    • https://underworldgear.com/admin/images/fckImg/file/famupotamivalonedufiges.pdfIn PDF document text
    • http://uitvaartverzorgingsindex.nl/images/uploads/70954212939.pdfIn PDF document text
    • http://dkkarsin.pl/img/upload/files/sinego.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/161334fc6594c7---dovek.pdfIn PDF document text
    • http://upservice.expert/admin/ckfinder/userfiles/files/kogesokonanumapemi.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/fcf823954ed682acdac23c8e0b8f7c96/lipidulim.pdfIn PDF document text
    • https://urology-andrology.com/userfiles/file/54947427671.pdfIn PDF document text
    • http://dallapietamarchisio.it/userfiles/files/niserinogubimepu.pdfIn PDF document text
    • http://xiangzhuan.tw/upload/files/wazepikuvunamiz.pdfIn PDF document text
    • http://industrialsupplies.pk/userfiles/files/99158105752.pdfIn PDF document text
    • http://61kidsclub.com/userfiles/file/tezafegin.pdfIn PDF document text
    • http://www.saito-ken.jp/userdata/file/feziwuzapor.pdfIn PDF document text
    • http://myrbacken.se/login/ckfinder/userfiles/files/56687320921.pdfIn PDF document text
    • http://skrutit-probeg.ru/upload_picture/file/76166874680.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=jameel+noori+nastaleeq+font+androidPDF 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_off0000c8b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8B6 19148 bytes
SHA-256: c8a7e68139efcb8445acc66a14f07a4778f1d4e44e09d424a4c6ce446d4ed7a7
font_01_sfnt_off0000fa30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA30 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011247.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11247 10652 bytes
SHA-256: e02bcfee40da5c8c5b8dfe85d9f336fc99cfd529a24bdb7834cf88820a34b18c