Malicious PDF — malware analysis report

Static analysis result for SHA-256 36791f82c62997d8…

MALICIOUS

PDF

71.1 KB Created: 2021-09-26 01:49:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c5cfa3169e15792e14130c4ac369531f SHA-1: 7e3863952eb7ee2f0f2d3b035de250aefbf7bce5 SHA-256: 36791f82c62997d878f69acb3ba75076c3b8e5547d5226f56aa1fa76a0536603
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to numerous URLs, many hosted on compromised CMS upload directories or disposable domains, designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics suggest an attempt to trick users into downloading further malware or visiting phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://smidgel.ru/uplcv?utm_term=18+bangla+books+pdf+free+download
    • http://ux-school.ru/files/files/rimew.pdf
    • https://merlak.ru/userfiles/file/92940052699.pdf
    • https://bilegt.mn/userfiles/files/45009558059.pdf
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161419eaadaa04---3870083123.pdf
    • http://songhakbbq.com/uploads/files/92028376033.pdf
    • https://bcm.es/files/galeria/files/67887253942.pdf
    • http://chistogood.ru/admin/ckfinder/userfiles/files/55761679763.pdf
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/m1u75nc0np744cbtdr0jbl1het/67941815019.pdf
    • http://diadiemvui.com/upload/files/fojerunevun.pdf
    • http://lctrading-gmbh.com/ckfinder/userfiles/files/mixuvuredemarutinozadofo.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f221701ab6---finumozino.pdf
    • http://www.adarshvidhyasankul.org/userfilesfile/87922946164.pdf
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d17eaad33---4373513856.pdf
    • http://laibros.com/ckeditor/userfiles/files/noduwi.pdf
    • https://chptravel.ir/data/file/73976916787.pdf
    • http://vimar.ua/userfiles/files/sipoluzojaji.pdf
    • http://jayeonrak.com/upfile_editor/2021/files/91408605632.pdf
    • http://tribo.kz/userfiles/File/wiwixolamijovasugoduxibi.pdf
    • https://pasarangroup2.com/contents/files/pikidowajafosililozubakag.pdf
    • http://etabetasurvey.com/userfiles/files/vugifilenewafegetediw.pdf
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/16143c0c3ec60a---99714540778.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/161420a6bc2413---bipasepuvaje.pdf
    • https://used-machinetools.ro/app/webroot/files/userfiles/files/99346821823.pdf
    • https://y3stwk65l-mn9.com/contents/files/jeparam.pdf
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614f4bf30d1c6---55356664689.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_off0000b237.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB237 16792 bytes
font_01_sfnt_off0000ca49.bin
ca0274bc0d5b62be77d4ba9462763a8f39b5dbad11da47a84c98a700c1436ffa
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA49 16828 bytes
font_02_sfnt_off0000f59d.bin
fc5467fb8358ed52452fad16c1bb10eb47820d160ab1a04c38b519869c1459ae
pdf-font-stream PDF embedded font (sfnt) at offset 0xF59D 10964 bytes