Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec2e4325a69a99fc…

MALICIOUS

PDF

69.4 KB Created: 2021-09-17 12:04:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f948dcc8efe58e57a607ab9468de92d5 SHA-1: f937df97fc07d7bc9addaf7b019099cc879b0c7a SHA-256: ec2e4325a69a99fca64719e6f0d301f3bd1e76ee42c18676fe389d44a0b4c300
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, suggesting a link farm or SEO manipulation tactic. The ML classifier strongly indicated maliciousness, and the presence of external URIs and compromised CMS links supports a pattern of potentially harmful redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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://scantech3d.com/files/gibedidiseso.pdf In PDF document text
    • http://ghalemdi.com/userfiles/file/2130933729.pdfIn PDF document text
    • http://generale-bureautique.fr/gdb/files/file/vavavugadori.pdfIn PDF document text
    • http://dyglas.com/userData/board/file/46685343322.pdfIn PDF document text
    • http://moiarchitekci.pl/pliki/file/bejavubujifefewifasajigud.pdfIn PDF document text
    • http://thermcom.cz/userfiles/file/fapivoxotowug.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16140738e7d635---zuzerexedufige.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b49f791591---tevipezaxorolegu.pdfIn PDF document text
    • http://china-engine.net/ckfinder/userfiles/files/zavozisaxufetovute.pdfIn PDF document text
    • http://dsfly.com/uploads/files/gezogofazujogutinadub.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/devanumelaloxu.pdfIn PDF document text
    • http://speckrepeg.by/UserFiles/files/5063390436.pdfIn PDF document text
    • http://dgelc.com/userfiles/file/20210908144657.pdfIn PDF document text
    • https://thietbigas.net/media/files/39363718003.pdfIn PDF document text
    • http://www.clc-engineering.com/siteuploads/editorimg/file/5916261619.pdfIn PDF document text
    • https://textmakareknutsson.se/upload/image/nadejiluxiwijori.pdfIn PDF document text
    • https://lentes123.com/aym_image/files/85292346727.pdfIn PDF document text
    • http://digivideos.net/ckfinder/userfiles/files/64435802823.pdfIn PDF document text
    • http://topbuild.net/content/xuploadimages/file/89015980244.pdfIn PDF document text
    • https://xaydungdonggia.com/app/webroot/files/images/pages/files/8310822547.pdfIn PDF document text
    • https://rimsball.com/ckfinder/userfiles/files/8843994186.pdfIn PDF document text
    • http://hzeiger.com/userfiles/file/zulubunanon.pdfIn PDF document text
    • http://ezclasssites.com/var/wwww/dev-ezclasssites-com/data/files/toxavuwob.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16142a4accfbbf---45985063859.pdfIn PDF document text
    • http://tieuhocsongphuong.hoaiduc.edu.vn/ckfinder/userfiles/files/funorodozubowiz.pdfIn PDF document text
    • https://nhahangthanghuong.com/uploads/files/mizisazamekewilapavo.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210916_89DB3F22010D7AB2.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=clash+of+clans+hack+apk+free+downloadPDF 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_off0000b372.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB372 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB89 10736 bytes
SHA-256: 2e1ca49794643078bb5b918f4ff057923c3142c4b3ca26466e9fbb6d50c79eac
font_02_sfnt_off0000e43a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE43A 14400 bytes
SHA-256: c1acb87bfffa6aee85f536b717ec954e592797ae473f4bd2d9ccf44bebcbbd2f