Malicious PDF — malware analysis report

Static analysis result for SHA-256 23b78ebc252fb5ca…

MALICIOUS

PDF

68.9 KB Created: 2021-09-30 12:47:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 018284c0514907c782c574163c67ada6 SHA-1: 901694263e79410d3a39174d5134abe16e209cbd SHA-256: 23b78ebc252fb5ca03eeebb8e8b41218850322af0f0b1cc1fd2b362de90242ee
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting, 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. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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=zelda%27s+lullaby+ocarina+tab PDF link annotation
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16137a57df3e06---xatopugetajusivon.pdfIn PDF document text
    • http://yuhenganquan.com/userfiles/file/20210913052130_311622769.pdfIn PDF document text
    • https://emilline.dk/ckfinder/userfiles/files/92264112818.pdfIn PDF document text
    • http://saveondealz.com/ckeditor/ckfinder/core/connector/php/uploads/files/40968209172.pdfIn PDF document text
    • https://www.gico.ge/ckfinder/userfiles/files/nogebejovitomidapipefipu.pdfIn PDF document text
    • http://nakamurasangyou.jp/app/webroot/uploads/files/fotaxuzimotiduba.pdfIn PDF document text
    • http://multi-accueil.fr/ressource/site-image/files/87255057181.pdfIn PDF document text
    • https://podgoricki-klub.me/userfiles/file/voxamamapinodiz.pdfIn PDF document text
    • http://zenithmetals.com/files/23831146198.pdfIn PDF document text
    • http://tiramisu-o.com/yamituki-n/uploads/files/88469377110.pdfIn PDF document text
    • http://odontoflash.eu/userfiles/files/24751502708.pdfIn PDF document text
    • http://gdfsztal.com/uploadfile/files/2161938652.pdfIn PDF document text
    • http://ambulatorioveterinariocamali.com/userfiles/files/61524558258.pdfIn PDF document text
    • http://opusbiz.kr/data/editor/file/19268889786133b18d45aef.pdfIn PDF document text
    • http://mywayrtk.org/userfiles/file/16253336883.pdfIn PDF document text
    • http://tongkhomica.com/upload/files/mawivip.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/16139717877417---maxabojefivobir.pdfIn PDF document text
    • https://menu2uplus.com/images/file/8075840090.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161371c1e6cbdb---88040973110.pdfIn PDF document text
    • http://auburn-properties.com/userfiles/files/geziboromo.pdfIn PDF document text
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/lidex.pdfIn PDF document text
    • https://epgeptech.hu/ckfinder/userfiles/files/fukifinuvemupuxu.pdfIn PDF document text
    • http://creptiles.dk/userfiles/file/girup.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_off0000ae7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE7E 15248 bytes
SHA-256: 63ffb98ab0b29624c841215e2048f29dbdb1ce6e0d3c7b45976074fa542a71fc
font_01_sfnt_off0000d568.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD568 10716 bytes
SHA-256: 45bda002cf75b7fc1f41aa61db020ce743957690e53fdb7769d46e5854240947
font_02_sfnt_off0000ee31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE31 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1