Malicious PDF — malware analysis report

Static analysis result for SHA-256 d63ab36fa14b93af…

MALICIOUS

PDF

76.6 KB Created: 2021-09-03 02:13:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 021866c6ba084c99893fabd859b44e62 SHA-1: a2c0c0cb8b023cbdf3038035d8ec68ebfcfddd64 SHA-256: d63ab36fa14b93affe4122cd553759352237ac1c19446aaf4fed44e7bd03f6d3
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier strongly indicated maliciousness, and the presence of embedded URLs further supports a phishing or malware distribution attempt. No scripts were extracted, but the overall structure and URL analysis point to a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://queure.ru/uplcv?utm_term=distributive+property+of+multiplication+for+3rd+grade+worksheets PDF link annotation
    • http://akcjonariusz.com/UserFiles/file/vateradezavisabapa.pdfIn PDF document text
    • http://papinchess.ru/userfiles/file/2995147417.pdfIn PDF document text
    • https://kisikana.hr/userfiles/file/75565273689.pdfIn PDF document text
    • https://xyoaa.org/sites/default/files/files/nofibamosekuboliv.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16070da0445daa---xulutimejerubefes.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/vixizi.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607f40ec4b7d7---8280292335.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b9c28f2ec0e---63365118807.pdfIn PDF document text
    • http://archiwum.wyryki.eu/admin/ckfinder/userfiles/files/pasiluzawum.pdfIn PDF document text
    • https://www.perfumista.co.uk/wp-content/plugins/super-forms/uploads/php/files/e9e0bb50ec954fafc9592a4eec72913c/5533237169.pdfIn PDF document text
    • https://vydavatelstvoklett.sk/userfiles/file/4021203124.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608accbe4187b---44353817018.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608694d1eaebe---luzab.pdfIn PDF document text
    • https://madspot.dk/ckfinder/userfiles/files/gewubosemerekizovatoj.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/67bbce849442cf4940d0d0d0db293178/ladole.pdfIn PDF document text
    • http://psmpetcare.com/clients/76030/File/wajonebodanuvab.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/b172624be855dc0cb27c5a78c1ce2dac/23009612436.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611c4fca4357b---lufejasovug.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/b1fb261acf1f71d93c2c782e757b724b/96746616816.pdfIn PDF document text
    • http://kukubara.com/zdjecia/file/kisula.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe08c58c4a---xazuwikewogalijex.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/o5ghu73s6anq3c874knhglt9vj/34777175167.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/3g2ugfffanhdnoaq65j81km8f7/gijefazopusiri.pdfIn PDF document text
    • https://tezerwatch.com/file/upload/files/06-15-12-10-35-18.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_off0000c297.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC297 11840 bytes
SHA-256: 1bbea9c9a9bc0563d92be7070d6a6f29b5b52919e5cf8843981aefbb32ed505d
font_01_sfnt_off0000de7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE7E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f690.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF690 17436 bytes
SHA-256: 256e516f046acacc11f2cf68531781c8ec41556ce417560f80a2c80fd4f272fe