Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d246c3fa9fc5949…

MALICIOUS

PDF

79.6 KB Created: 2021-09-11 20:12:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a1703b713d3c3b704bbd4af0aef2e1b5 SHA-1: f17fe01756ec1700b1a61d37d9279112192e79ed SHA-256: 6d246c3fa9fc59494a651795e78bfc85c35d6a0065012afed28de3d6c569f00f
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a large number of embedded URLs, many of which point to websites hosted on compromised CMS uploads or disposable domains. The ML classifier strongly indicated maliciousness, and the structure suggests a link farm designed to redirect users. While no scripts were explicitly extracted, the PDF format can embed JavaScript, which could be used to facilitate these redirects or other malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://pixomot.ru/uplcv?utm_term=how+to+transfer+data+to+memory+card PDF link annotation
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/stn1e7qchhtl1aqm7stog7sm7l/22827144132.pdfIn PDF document text
    • https://aradmissions.com/ci/userfiles/files/97518795319.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/35260293088.pdfIn PDF document text
    • http://murasakijr.com/uploads/files/gatoto.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/64f39495c876cfe54e07131bc68a74d4/mawemor.pdfIn PDF document text
    • http://xn----7sbezcba9a5aggb3j.xn--p1ai/ckfinder/userfiles/files/xorinam.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16134f8f88f2df---pumobejonufosug.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161365f3a9600a---24548405758.pdfIn PDF document text
    • http://inbiosa.eu/static/cfiles/files/buwagoru.pdfIn PDF document text
    • https://seeandhearbetter.ie/img/shop/contents/13851482479.pdfIn PDF document text
    • http://maivietnamesecotati.com/uploads/files/zumobavo.pdfIn PDF document text
    • https://macroedunet.com/userfiles/file/majenujujovonipanexuvow.pdfIn PDF document text
    • http://pataibicaj.hu/userfiles/file/50144139466.pdfIn PDF document text
    • http://joy05.com/_UploadFile/Images/file/fidokuziw.pdfIn PDF document text
    • https://auto826.vnpec.xyz/uploads/files/denufipotepidubowaz.pdfIn PDF document text
    • http://goang-hann.com/uploads/files/202109042359382528.pdfIn PDF document text
    • http://gibkrakow.pl/uploads/files/bosojuromubelovo.pdfIn PDF document text
    • https://siriusdynamics.com/assets/uploads/files/22165713404.pdfIn PDF document text
    • http://di-tech.kr/fckeditor/userfiles/file/10287545699.pdfIn PDF document text
    • https://a-metal.e-giant.net/archive/file/files/wodufurasogipaguxokuf.pdfIn PDF document text
    • http://ktcz.eu/files/files/78307380122.pdfIn PDF document text
    • http://elturo.ru/img/upload/files/wujedoparujirusirejegume.pdfIn PDF document text
    • http://zafirkort.com/uploads/files/liwurexavofew.pdfIn PDF document text
    • 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_off0000d53a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD53A 16760 bytes
SHA-256: 75a5969afcb3df26ca2c6f6d81d808fb9774fc0ead25dfe1961ef176d0850bdb
font_01_sfnt_off00010025.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10025 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001183c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1183C 10692 bytes
SHA-256: 55444f6399ec360f05617117630aa3c1049082696e3b0612b56cb38b5f6846ad