Malicious PDF — malware analysis report

Static analysis result for SHA-256 257dc775c6d0c650…

MALICIOUS

PDF

97.3 KB Created: 2021-08-01 15:55:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 13849b37d7f93f96f60a7bcabaa59aa3 SHA-1: 651fdf34665deaf3653bfbb5f33397da80dae25a SHA-256: 257dc775c6d0c650b8ceb6c8fa2ba6b6e369c7d671532dadbb6a5b4d4fb00dc2
156 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of URLs, many pointing to compromised WordPress sites, suggesting it functions as a link farm to distribute malicious content or phish users. The presence of external URIs and link farm heuristics indicates a clear intent to redirect users to potentially harmful external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9918

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://pixomot.ru/uplcv?utm_term=accounting+and+finance+for+bankers+macmillan+3rd+edition+pdf+free+download
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a87edc80d39---mutuzutupuguvud.pdf
    • https://www.litesourcenc.com/wp-content/plugins/super-forms/uploads/php/files/911f5c407748865e5b78c88873ac546b/pifogavezesozebozote.pdf
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/86a5054919ab15bb91b4b134e9372fbc/sojopifikeregadekipobe.pdf
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fff3fec4ac---45296458145.pdf
    • http://sskj.pl/userfiles/file/junukoxetoxilotipuj.pdf
    • http://tamker.hu/userfiles/file/12061364892.pdf
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c92eea1319a---bupugekewojixuzuxapaduwos.pdf
    • https://southernlightingsource.com/wp-content/plugins/super-forms/uploads/php/files/590062e1d9a917aaddeb100abbe83f42/8388201947.pdf
    • http://daindnc.com/fckeditor/userfiles/file/vasenofute.pdf
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/05fd3664faaf764b57b0bf4e9040660c/zaserij.pdf
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/520b75bd6ae52cfeab1cd8920ecb9476/43701588693.pdf
    • https://nadamasristorante.it/file/78519873129.pdf
    • https://noithatkuongthinh.com/uploads/files/92045673529.pdf
    • https://dongcohonda.com/userfiles/file/dediroxifusuxuxemuz.pdf
    • https://soltendance.com/stockages/files/tefixes.pdf
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/9538ba81791bb2c2b88dd9e6d00a1fea/pebeg.pdf
    • http://goldartline.ua/userfiles/file/vizubutitefulaxexip.pdf
    • https://renfrewareahealthvillage.ca/ckfinder/userfiles/files/zupuputazutefoba.pdf
    • https://monyetjoget.com/contents//files/43436124056.pdf
    • http://vigova.vn/Images_upload/files/48684081841.pdf
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/obtnfv4h82rfv0kf85m309iu15/mijov.pdf
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606da043800e4---26607102535.pdf
    • https://agroadvanced.com/app/webroot/newsletters/editor/files/tunatowole.pdf
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/u854si0l6ib3m195d5rp5kkk54/xupijul.pdf
    • http://energo-market.ru/sadm_files/74839337706.pdf
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b8109836c12---ruboxepu.pdf
    • http://seventyfirstclassof69.com/clients/60772/File/xaxixitapuz.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_off000114a1.bin
17b38913ce99ef8b2794fccfac5ed6a924ae65d6dd985721a6fa4f330a624b7f
pdf-font-stream PDF embedded font (sfnt) at offset 0x114A1 17656 bytes
font_01_sfnt_off0001429f.bin
eb0ec8c19f29ef568393cec32c166e3fc1ec0c186013f8fb737970a6fb7795e5
pdf-font-stream PDF embedded font (sfnt) at offset 0x1429F 11532 bytes
font_02_sfnt_off00015db5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15DB5 16792 bytes