Malicious PDF — malware analysis report

Static analysis result for SHA-256 93b2510abab07603…

MALICIOUS

PDF

91.9 KB Created: 2021-08-19 16:22:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f920cc3ffd465f11a2dd6e18a908f94d SHA-1: bc46557afd81892f8fbdebd13dd5133e67d3bdb0 SHA-256: 93b2510abab0760310f549c02a2eccdf914cb862f01717f265a11369056ee091
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised or disposable hosting sites. The presence of numerous external URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly suggest an attempt to distribute malicious content or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://k-yoga.org/file_upload/spaw_upload/file/20210525043259.pdf In PDF document text
    • http://krajinar.cz/soubory/files/rugosutesewov.pdfIn PDF document text
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087ba776fb99---5737420611.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4fb8526d4---rovowugegajeruzabakonev.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16094a14986cee---romomogituniwema.pdfIn PDF document text
    • http://meta-min.com/files/tenetirofonuzobuvo.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/270ac801808ad98b6fbfa1dda16fceb0/sagesumemevagufinixuwel.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/31ce4f9f8d2f5ff0411a6e9b9e0278ab/dunipulutobowopotuleg.pdfIn PDF document text
    • https://mimpi1pusat.com/contents//files/45270863291.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/podoranusuzobudutuvanopu.pdfIn PDF document text
    • http://studiorumeo.it/userfiles/files/7476030624.pdfIn PDF document text
    • https://perfecthospital.org/ckfinder/userfiles/files/xonavigivatokilixuwul.pdfIn PDF document text
    • http://scamps.biz/userfiles/file/fekeb.pdfIn PDF document text
    • http://spearsyounglegacy.com/clients/b/b2/b2c23f164518415ec8f3c1c8d0af542d/File/10790602157.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/e019d470ca8768efd6bfb48a0976e4b7/37782478720.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/s2j72p2i8ldce1mjarsi2kna1p/5361230100.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609bf890adf18---jolarutulixoz.pdfIn PDF document text
    • http://perfekttorun.pl/pliki/78733228672.pdfIn PDF document text
    • http://vipforiraq.com/userfiles/files/baxozomanukom.pdfIn PDF document text
    • http://artgraf24.pl/userfiles/file/zonolofoxodokalipi.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b9a8fb706a---zutewamorujemog.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/71b926fe95cae7f65eee22b48b791131/vifazazeruzinipinovubemex.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160f0f1207ba6e---zujujasob.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/fojakutidivuzorikafak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=biology+1+final+exam+study+guide+answersPDF link annotation
    • http://irodori.kir.jp/files/file/36169517867.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_off00010212.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10212 11204 bytes
SHA-256: 98535a793917dce638da161d090ee6918ae967447a287e82196b8f74970ee942
font_01_sfnt_off00011c3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C3E 17080 bytes
SHA-256: 538d8d03973db04aebc5f52af7b221b67372204478d7dd16b55d988e2c3da32a
font_02_sfnt_off000148eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1