Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4cfbdba3ccd6c28…

MALICIOUS

PDF

79.9 KB Created: 2021-09-16 01:17:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4558085c4668c713bdd7d50ab242fb1b SHA-1: f15fdad0c422ab93a9280c933634ef8f9788b57f SHA-256: e4cfbdba3ccd6c281114f0623b51d2b75d89ecd69a1e7f056a71894bdf8a3c2b
96 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting a link farm intended to drive traffic to potentially malicious sites. The ML classifier also strongly indicated maliciousness. While no scripts were extracted, the structure and URL targets point towards a malicious intent, likely for SEO poisoning or to lure users to phishing pages.

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 https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/051e3f529b64c213a4c159f024e06dd7/pozatepipefojafop.pdf In PDF document text
    • https://twinslock.com/ckfinder/userfiles/files/43290384342.pdfIn PDF document text
    • http://fogathajtohirek.hu/fckfiles/file/7721432242.pdfIn PDF document text
    • http://oawebserver.com/piceditor/file/febezixufapetazatu.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/pefuxij.pdfIn PDF document text
    • https://ehbo-oostkapelle.nl/userfiles/file/21974234996.pdfIn PDF document text
    • http://free-note.kr/files/fckeditor/file/100686184613716b589d97.pdfIn PDF document text
    • http://sayarbobinaj.com/file/90431209069.pdfIn PDF document text
    • http://ttc-investco.com/img/files/tevupewusul.pdfIn PDF document text
    • http://putzlappenborner.at/editor_up/54302494032.pdfIn PDF document text
    • http://redskap.ru/userfiles/file/walijokisekunopuforam.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3a9c441da---pejinurelimarazeme.pdfIn PDF document text
    • http://njchemland.com/upload/files/74199728301.pdfIn PDF document text
    • https://pharmawell.eu/ckfinder/userfiles/files/69817058771.pdfIn PDF document text
    • https://foodexgida.com/uploads/files/94152619412.pdfIn PDF document text
    • http://koppeika.ru/userfiles/file/wulaxosuzomivafefezadopof.pdfIn PDF document text
    • https://domilot.com/uploader/files/jiduximegasijabeb.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/db8193e3331180c848be6c8fa39377af/gezik.pdfIn PDF document text
    • https://elemental-ia.com/userfiles/file/vorev.pdfIn PDF document text
    • https://www.habitat-morvan.fr/ckfinder/userfiles/files/diwikenejunifulifugu.pdfIn PDF document text
    • http://musicincw.com/fckeditor/userfiles/image/vulujaruzalavowedero.pdfIn PDF document text
    • http://psychanalyste-gard.fr/ckfinder/userfiles/files/55400136589.pdfIn PDF document text
    • http://elektrostroy.kz/ckfinder/userfiles/files/tafuwaweji.pdfIn PDF document text
    • https://easresidence.ro/app/webroot/files/userfiles/files/tobokumegujif.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=streaming+anime+sub+engPDF 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_off0000d407.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD407 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC1E 10600 bytes
SHA-256: 284c5af116f883910d76c44b591c44bd8c7f5e2e394951d85e784a85aed11f29
font_02_sfnt_off00010452.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10452 17492 bytes
SHA-256: ddff1cfb1c2841fb22d84a6d616823a7fb8b835e5eb2ab6e1b22dc136cf5542d