Malicious PDF — malware analysis report

Static analysis result for SHA-256 d239fecf3aec23f3…

MALICIOUS

PDF

81.6 KB Created: 2021-09-05 12:46:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3b7dd92d12dae98532716cef882896b2 SHA-1: a673c27b370adf6140fe4aa794352a2a6ff8ffe9 SHA-256: d239fecf3aec23f3170fbb923248630d1966ae3782fca185379e8b4d8548fb2f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The use of compromised CMS upload directories and SEO-optimized link farms further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://archism.ru/uplcv?utm_term=chesterton+the+everlasting+man+pdf PDF link annotation
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/boferonupowozuxir.pdfIn PDF document text
    • http://m-s-g.ru/userfiles/files/wakumaxorowobetoxatowudir.pdfIn PDF document text
    • http://xn--dlek-5qa.com/admin/UserFiles/file/vudatuwamureribonir.pdfIn PDF document text
    • https://branchennachweis.eu/userfiles/file/3004605740.pdfIn PDF document text
    • http://sobsai.com/ckfinder/userfiles/files/86602744754.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/8pb8o5mipf7bjcqqk3dmqmsmpt/jonabovedijegiti.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/9ejjmc0v6m62ir5tj8rjnlfu5f/82993564252.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/3e34df62d9c8ac340294e3ac5adf701d/47558673173.pdfIn PDF document text
    • https://egf.tw/test2/images/file/zaxewapuxofidasunu.pdfIn PDF document text
    • https://aykutemlak.com/upload/ckfinder/files/75532929083.pdfIn PDF document text
    • http://www.houstonorientalrug.com/ckfinder/userfiles/files/61704134038.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084230d2c7ae---67174361364.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/1r51177tuedh11jf19jgea68l4/pivujomuxibu.pdfIn PDF document text
    • http://grabnerestriche.at/46864074310.pdfIn PDF document text
    • http://sicilyontable.it/userfiles/files/povepok.pdfIn PDF document text
    • http://murphysbeads.com/clients/54316/File/tufixanexoxarofi.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/55778164927.pdfIn PDF document text
    • http://bronia.org/userfiles/file/navuronuzimapimeborolez.pdfIn PDF document text
    • http://oaklandscreche.ie/userfiles/files/xivadurud.pdfIn PDF document text
    • https://adikketiga.com/contents/files/winatanerurutijolasep.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607171df7862f---mebebatigep.pdfIn PDF document text
    • https://acrgruppe.de/userfiles/file/pikabutodowidavufatogit.pdfIn PDF document text
    • https://careersourceokaloosawalton.com/files/public/xipusudugagilobik.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/35bqvjo29hog1d6hd4gtcm9ke0/jawuboj.pdfIn PDF document text
    • https://krossi.ru/images/content/files/xulobegofimofere.pdfIn PDF document text
    • http://mebelhotel.ru/images/news/file/90096509581.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_off0000da7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA7A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f28c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF28C 17180 bytes
SHA-256: 9434b35c088d40f09415062a5527df7b227af3e41ee846d616024e6a1eadd001
font_02_sfnt_off00011f97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F97 11040 bytes
SHA-256: 9a539e85d883d5d081003d6d17d27359b2c4c87440ec6b58b71719419e9b8beb