Malicious PDF — malware analysis report

Static analysis result for SHA-256 145cd28a2b3492b4…

MALICIOUS

PDF

73.5 KB Created: 2021-09-16 17:58:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4b60bd74cdb5a28bdd7f8caf3a8ee64b SHA-1: 425f02f76cbef37b2d06388e36b06da3bc7293bd SHA-256: 145cd28a2b3492b49265355b3454be6b2fbfd1e964fdd1364d771a7c4a4f5435
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to various websites, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly indicate that this document functions as a link farm. The ML classifier and ClamAV detection further support its malicious nature, likely serving as a lure for phishing or malware downloads.

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://pistant.ru/uplcv?utm_term=tubemate+latest+app+download PDF link annotation
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ec673cd8e---20070866483.pdfIn PDF document text
    • https://cuacuonbentre.com/upload/files/62673334689.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140497f9ff02---puretebotabukorep.pdfIn PDF document text
    • http://xn----7sbbgprpk7biiq.xn--p1ai/admin/ckfinder/userfiles/files/72937980310.pdfIn PDF document text
    • http://joyear.com/ckfinder/userfiles/files/73783681001.pdfIn PDF document text
    • https://chung-pei.com/userfiles/file/xekiwafiw.pdfIn PDF document text
    • http://auto-rad.pl/userfiles/file/dekajosizifun.pdfIn PDF document text
    • http://yuanhebiotech.com/upload/files/remezidelasus.pdfIn PDF document text
    • http://4rrecycle.com/files/file/77195401947.pdfIn PDF document text
    • http://tuivaivietnam.com/uploads/files/powudejojifu.pdfIn PDF document text
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/49a1702b7fc1895d8a3da506261b473c/26410331423.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/gusatawisuwuk.pdfIn PDF document text
    • http://cnwt.mgo.cool/upfile/files/2021/09/13/poxudun.pdfIn PDF document text
    • http://aktifimmo.lu/userfiles/files/34041892263.pdfIn PDF document text
    • http://lulanjina.net/upload/files/figibusuzejagikit.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/96g72olcflno2f7467ufd571j7/fupegok.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/4f76206c86c1cd6a34512c27210cb729/62735637347.pdfIn PDF document text
    • https://pleasanton.com/wysiwygfiles/file/volitewon.pdfIn PDF document text
    • http://cs-web-design.de/ablage/userfiles/files/jawerojutor.pdfIn PDF document text
    • https://aodaixuan.vn/app/webroot/upload/image/files/tomagewepinafexuwovumamax.pdfIn PDF document text
    • http://xn--9i1b14lwsg1seumdzsx.com/upload/fckeditor/file/zesekatomo.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_off0000beb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEB6 10652 bytes
SHA-256: 3854d095546fae3cb0e2ffe7d59b351e36a32001b6fcb21e9101440b9d9e9be5
font_01_sfnt_off0000d6f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F9 16324 bytes
SHA-256: aae9f98e0d96054ede67f529d1a0b70ee745fb233c874c0e0491f2ec8b48369a
font_02_sfnt_off000100cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100CF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1