Malicious PDF — malware analysis report

Static analysis result for SHA-256 423c53bcebb9b900…

MALICIOUS

PDF

84.9 KB Created: 2021-07-16 13:58:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2a57d52f66fff8c15a1e3eb69c465748 SHA-1: 1fd24e3c532e7a3616033ce621e7a60d3235b8bd SHA-256: 423c53bcebb9b9009b1ad693e1b6cf7e7423878f2e4d0c75ef0a06045f2677ae
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as a link farm and a potential phishing or malware distribution vector. It contains numerous links pointing to compromised WordPress uploads and disposable domains, suggesting an attempt to lure users to malicious content. The ML classifier and ClamAV detection further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://nomylo.ru/uplcv?utm_term=early+child+development+and+care
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b87a3017857---tomoxaf.pdf
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16086a573eee8e---norikidagubajiwadu.pdf
    • http://kiuanai.com/userfiles/file/kelefofamixox.pdf
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/9f4864b7e5257c3a6eb327219722e33c/96045004140.pdf
    • https://fertilizergranulatorprice.com/d/files/jegebinifarawokogifupabev.pdf
    • http://bluecars.pl/userfiles/file/58964062832.pdf
    • https://epiphanych.com/images/file/88849101256.pdf
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b460664c238---sewiwazojifizalasote.pdf
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609b4b94a02e4---jezipotilaporituzanewob.pdf
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/hju9p07go6faon4im15pa71ns6/94469353882.pdf
    • http://eska-lift.ru/userfiles/file/rapunafinawiden.pdf
    • https://bloomeng.com/uploads/23284232485.pdf
    • https://ildiko-szepsegszalon.hu/userfiles/file/76731746742.pdf
    • http://vina2002.com/uploads/files/moduxejez.pdf
    • http://vaikevai.com/ckfinder/userfiles/files/35251949713.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079388b9e30f---koxubixutu.pdf
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1c4ba355b8---sajukudivegosonawiti.pdf
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/nmgtlqst09uj95gtcuro4ppie2/xasosin.pdf
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac8eb3e80e5---rajojolisofati.pdf
    • https://lee-trading.tw/archive/upload/files/33163951820.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609a1a93d1737---jugigigevawonobi.pdf
    • http://lucann.com/Upload/file/pakapebeku.pdf
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/ik8b5lgatcj5oeca8d1a4j4ukh/melejip.pdf
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b977fb9b454---noduguxiboxivafegod.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16084a6d36ad3b---silabegujaketupabij.pdf
    • https://dacinsara.ro/fckfiles/file/povakurabad.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e78d.bin
5e644722454ff121bca75e9f8023b2ec7b1e5a58300914f662078ddb089365f3
pdf-font-stream PDF embedded font (sfnt) at offset 0xE78D 17624 bytes
font_01_sfnt_off000115a6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x115A6 16792 bytes
font_02_sfnt_off00012dbd.bin
c331477e348e2be219d72c673b6f4c741a55efbf7882cdb4527db3078774e885
pdf-font-stream PDF embedded font (sfnt) at offset 0x12DBD 10776 bytes