Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d2e3bc96de1399a…

MALICIOUS

PDF

88.7 KB Created: 2021-07-06 19:43:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 25f52058d89011621a4d08c4649ffb80 SHA-1: eebafc1445512d9791af70d823bfbdaff4293413 SHA-256: 5d2e3bc96de1399af3816206b70141a864b31b5bad31426b46614d6b09102927
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file identified as malicious by an ML classifier. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm for SEO manipulation or to distribute further malicious content. While no scripts were explicitly extracted, the PDF structure and the nature of the URLs indicate a potential for malicious redirection or exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://thuaphatlailongthanh.com/upload/contentFile/minhchau/file/38819235710.pdf In PDF document text
    • http://zgkimsteszew.pl/img/upload/files/vewigasemegivodiporerub.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/f5ddf652e8ce8455ba9c790ebc9cc5a9/43082788629.pdfIn PDF document text
    • https://puntoagricoltura.it/file/vebakididurirevugasabe.pdfIn PDF document text
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/3r8b9opv9q8kcpig0om97b5e07/7783484395.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b172e3d31d9---koboladumisunizesado.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a5c6b720381---15807469208.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091d58335e0a---37541717479.pdfIn PDF document text
    • https://balajihighfields.in/userfiles/file/dotavamida.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/31d6309eea89ad2dffe9f11dcdeaa0e7/gutigulixajewetapibagape.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/f2r26670fefpft3jumts8i5cs7/sefovijesori.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ca438f4ec9f8d5275a6a86506d82a161/bupuvu.pdfIn PDF document text
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/54n9p9tdc2miqqn7obacb92021/tesosuvos.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c756f59f69c---39700053785.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e0b899f17b9---71146567560.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d97264626d---wexisirumufobud.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608107cf8a0bf---79113225572.pdfIn PDF document text
    • http://kamerton.nl/clientfiles/11670415496.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4359f87cf0---69867564821.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/c8f8dd0b0f72c3a8a056eddcd48e814e/95595088723.pdfIn PDF document text
    • http://flgr.ru/files/files/65431242865.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16091e07105bed---xugagubaguluvixova.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160825ad28051c---pikufaxajatotel.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160718b11f0b70---30507199722.pdfIn PDF document text
    • http://myexamadvisor.com/fck_uploads/files/33121132715.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080fc3842876---9844234322.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=how+to+use+screen+recording+in+iphonePDF 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_off0000f562.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF562 10760 bytes
SHA-256: ec7a6fb480a95bd7c1baa1ff100f4dea4b28fee0131dc14a8b14f2ccb4cd0774
font_01_sfnt_off00010de3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DE3 17420 bytes
SHA-256: f5b6766a98e8863471423949607430561ac7af766dd28534bd7c791288ff7fd4
font_02_sfnt_off00013b34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B34 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1