Malicious PDF — malware analysis report

Static analysis result for SHA-256 03b99bd278b50547…

MALICIOUS

PDF

92.1 KB Created: 2021-09-05 11:00:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 4e35739026d0cfb8d1acc3c0532d0310 SHA-1: fedb814369ea3524427437d7da5eb910b34bbf05 SHA-256: 03b99bd278b50547f5476ee9395680759dee2f41228e1cde51d4335be4779bcf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites and disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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 https://laborke.ru/uplcv?utm_term=meaning+of+bounded+rationality+pdf PDF link annotation
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/vuko035qpmgpl5bpak1o83hjm5/90743244156.pdfIn PDF document text
    • http://itineraire-consulting.com/ckfinder/userfiles/files/95546702426.pdfIn PDF document text
    • http://group-anons.ru/userfiles/files/lesawuwakeseruma.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6949fd8915---jirukogowezazorazomike.pdfIn PDF document text
    • http://pchs1967.com/clients/b/b3/b38b0c0be7ceca4b309dcb684d78a7c5/File/sutenixofetixifiw.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bc90312353d---pemumepokesepajorixar.pdfIn PDF document text
    • http://studiotecnicomancini.eu/userfiles/files/vupufebigamugowuno.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea74f5e940---9521622159.pdfIn PDF document text
    • http://hyunbulsa.org/~ewedd2/userfiles/file/40640863046.pdfIn PDF document text
    • http://chikatere.com/Upload/files/vifutiwiru.pdfIn PDF document text
    • http://strelnicebudejovice.cz/userfiles/file/90243504623.pdfIn PDF document text
    • http://kukubara.com/zdjecia/file/90643963170.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/87ae7d7138024d6ee07e8568a9d6b8f9/6642319840.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160798804a1618---6585585580.pdfIn PDF document text
    • http://d4squebec.com/clients/f/f5/f58105ca183540932673f5bf18e62671/File/tisonuxidesabuxup.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16083f0dd9f6f7---48669793214.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1610830d70cf69---kizobagotaxororet.pdfIn PDF document text
    • http://teranor.com/ckfinder/userfiles/files/jutudovakupis.pdfIn PDF document text
    • http://www.dereformasenalicante.com/archivos/files/79080993166.pdfIn PDF document text
    • http://wijnhuis-vaessen.nl/site/data/ws/files/wiresubivazowekasagudix.pdfIn PDF document text
    • https://dolupin.com/calisma2/files/uploads/dekufesibabotegogasunixub.pdfIn PDF document text
    • http://lauraestetica.com/userfiles/files/nobovezidur.pdfIn PDF document text
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/cfe734a41a0e17760eb7d78eb0303916/73112564392.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_off00010036.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10036 10852 bytes
SHA-256: a1ab5931bdd42788c7d23feb7bb596ee8d2b378033468bd0a0c18019177c41d6
font_01_sfnt_off000118f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118F7 18652 bytes
SHA-256: c35ede048b883ff03fecdf532064659d1d29825f9818937b95f656692b54aab4
font_02_sfnt_off00014a3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A3B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1