Malicious PDF — malware analysis report

Static analysis result for SHA-256 23ae600989855e15…

MALICIOUS

PDF

73.7 KB Created: 2021-09-18 12:03:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 663eb04d06ea6720cfe7ecd709ce6cc6 SHA-1: 16962182ff8021b860db88f04c61d7466f4dbdd0 SHA-256: 23ae600989855e15182740e2fdf74cb5d3811271f14775c01ec3284b053cb4c0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing or trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to potentially compromised WordPress sites and disposable hosting. The embedded URLs are likely used to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://medvor.ru/uplcv?utm_term=os+android+laptop PDF link annotation
    • https://onutglen.com/caningest/images/file/25203235663.pdfIn PDF document text
    • https://nirkongrp.com/ckfinder/userfiles/files/ralelorixikikotibomireto.pdfIn PDF document text
    • http://khangvietdn.com/uploads/file/47586001975.pdfIn PDF document text
    • http://applecentervn.com/uploads/image/files/48019968985.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/b4617ea81ae94474cdb208ae2b68a594/vazewopomesiviremi.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/njakc421k1nuuhf2t854gajs39/govonipanugudub.pdfIn PDF document text
    • http://bibliotekaszamocin.pl/img/upload/files/vixamuko.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/girejazuwegevuzol.pdfIn PDF document text
    • http://hostingureitings.lv/uploads/userfiles/files/mibesiliganilegusip.pdfIn PDF document text
    • http://gioiacompany.net/images/upload/file/69345680424.pdfIn PDF document text
    • https://alev.az/userfiles/file/32513711723.pdfIn PDF document text
    • http://wiskind.com/filespath/files/20210907234657.pdfIn PDF document text
    • https://eko-briketes.lv/userfiles/files/22748161921.pdfIn PDF document text
    • http://gaestehaus-am-erlkoenig.de/img/editor/file/21338090007.pdfIn PDF document text
    • http://baobianhkhang.com/upload/files/xanajoz.pdfIn PDF document text
    • http://tetraeng.it/userfiles/files/kudofovovomojuvusetamopo.pdfIn PDF document text
    • https://butagallery.com/userfiles/files/fabitotamufenewasofevafu.pdfIn PDF document text
    • http://srmtteaparty.com/uploads/files/202109070427362747.pdfIn PDF document text
    • http://ydyb.com/filespath/files/20210903110730.pdfIn PDF document text
    • https://billionbosses.com/ckfinder/userfiles/files/49486995014.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614592a2b8dad---37330555811.pdfIn PDF document text
    • http://inspiredindianfoundation.org/uploads/luzazuvim.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/18567932180.pdfIn PDF document text
    • http://tetobox-budapest.hu/uploads/files/69582634447.pdfIn PDF document text
    • http://abwjefferson.com/uploads/files/12240822304.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_off0000bfe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFE0 16320 bytes
SHA-256: f4eaf55dc26aa47e1fbbac233e3c343ecfb3cf0cf7aa9dd000df8de3c8f4cf82
font_01_sfnt_off0000e9ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010203.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10203 10276 bytes
SHA-256: 7a69aab85face9cb55fe177de74f9f98f8833ebc2fa7bd670bcd61a0dbdda1e7