Malicious PDF — malware analysis report

Static analysis result for SHA-256 79bd960da2c624e0…

MALICIOUS

PDF

82.2 KB Created: 2021-09-05 19:54:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: b89167bdc5085bdc3197ca6eb2720d14 SHA-1: 5ced79d18eb03e33aa1e39788230fdec5d230f6e SHA-256: 79bd960da2c624e09c5e80e8c385faea9790021cf67a09b2c3a19d31ca8e2f08
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to potentially compromised WordPress sites or other disposable hosting, likely intended to lure users to phishing sites or download further malware. The PDF structure itself does not contain readable content, suggesting its primary purpose is to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://oniceh.ru/uplcv?utm_term=catalago+eudora+em+pdf PDF link annotation
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/e3898p65opm9lm0jqmub9bpdpu/12993452228.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/4ojh78rce2121js5rclv71o0j3/tepovefibudafi.pdfIn PDF document text
    • http://spadhotel.com/basefile/spadhotelcom/files/93393117928.pdfIn PDF document text
    • http://sllight.ru/design/img/upload/file/tetudimepusatalago.pdfIn PDF document text
    • https://iwnta.com/userfiles/file/baziwofiromimonoditubosuz.pdfIn PDF document text
    • http://gourmethousemacau.com/UploadFilesfile///potujebagetokevuroguja.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/iomllv9e0p1jb3sgqi2i4u3mjt/2643416966.pdfIn PDF document text
    • https://renesens21.com/ressources/upload/files/2086127976.pdfIn PDF document text
    • http://kenshopvn.com/uploads/files/62054605986.pdfIn PDF document text
    • http://labellebeaute.com.hk/ckfinder/userfiles/files/satutewunudorumogugilipo.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/74f0ec5ce96d3270bb29c31418bca31b/lezujipefewaxosokonerad.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/04ec78c34281269656d73f36b393847a/vorugupanuxidojejimuzib.pdfIn PDF document text
    • http://mariekevanvlierden.nl/survey/userfiles/files/643225799.pdfIn PDF document text
    • http://eegbiofeedback-leszno.pl/userfiles/file/mibewivinobibatibub.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f202c26e14---kokobiwebexonofa.pdfIn PDF document text
    • http://aeronautike.com/userfiles/file/1781414608.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/ad84bd3cde78dd46faffc22719552b67/zawanasasefutoko.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/2377fcd6e96586080192ab512058dccf/duxolexexolanavotedugid.pdfIn PDF document text
    • https://myphambambi.com/webroot/img/files/62400490794.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16078c43e8194c---72794304832.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160e81c0d88c73---pazefavekamupox.pdfIn PDF document text
    • http://vodnik48.ru/content/file/91470707482.pdfIn PDF document text
    • http://daechienglishpark.com/ckfinder/userfiles/files/zopor.pdfIn PDF document text
    • http://american-security-inc.com/assets/ckfinder/userfiles/files/moxebelawivawusikuvetoj.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_off0000d84d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD84D 10608 bytes
SHA-256: 1b6256137835487b0d75ac10f0420ae81b13ede102834efea093364973cfe283
font_01_sfnt_off0000f069.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF069 18928 bytes
SHA-256: 2a7fe0445ce1dd0cb36765037120c5cce96469e237df14fb24d5693e3d50538f
font_02_sfnt_off00012148.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12148 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1