Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf10faff16a50a99…

MALICIOUS

PDF

80.8 KB Created: 2021-10-05 22:15:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 8ce565b773e61ea6ad23e4fe8f0195e4 SHA-1: 19bd8db0f59352c74bbbbb3da3745285afe19d5d SHA-256: cf10faff16a50a9994e1e6772f97bce788cc64fbf87298e76145da62b379136c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm with numerous URLs, many of which are hosted on compromised WordPress sites or disposable domains, suggesting an attempt to redirect users to malicious content. The presence of 'utm_term' parameters in some URLs indicates a potential SEO-based lure, aiming to attract users searching for specific terms like 'fortnite mobile free download'.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://krisoc.ru/uplcv?utm_term=fortnite+mobile+free+download+for+android PDF link annotation
    • http://kleiberit.ru/files/file/lujudofodejasapaxarutu.pdfIn PDF document text
    • https://www.zolmedis.lt/ckfinder/userfiles/files/55891077816.pdfIn PDF document text
    • http://ageddfjtj.pretty-match.com/upload/files/91066184744.pdfIn PDF document text
    • http://pronobile.de/catalog/file/xexuxo.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/hjim50t5nuk5sh121qg19kqvjk/lowewadupepelomasalejos.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/vm488d8624cn6ae04dq7dq4onm/96413463381.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/16136efde8fb54---46592033564.pdfIn PDF document text
    • https://siriusdynamics.com/assets/uploads/files/18820124351.pdfIn PDF document text
    • http://ourgans.org/userfiles/files/tolabesufesupiruto.pdfIn PDF document text
    • http://xn--49s538bo8ux8c.net/userfiles/file/gorirarikemodutibad.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/24b8e8afe3be910756658f608b98870d/jezenun.pdfIn PDF document text
    • https://ateliersmq.com/pevron/www/img/file/7263881881.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/7381ac07ad1246687da1a8b8b2cf5949/zogadulaginizen.pdfIn PDF document text
    • https://psg66.ru/admin/ckfinder/userfiles/files/3656699115.pdfIn PDF document text
    • http://caratow.be/userfiles/file/nuguluwezusosugozupawuvid.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/rqcetfn4qrjk86msmc401l1jc0/44082080376.pdfIn PDF document text
    • http://prvugkh.ru/uploads/files/27030086641.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/t3d54u5m41imm8v703kp60enth/2686667930.pdfIn PDF document text
    • https://ascend.sut.ac.th/ce/2017/src/plugins/ckfinder/userfiles/files/3621709125.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c44f49bf71---82602833268.pdfIn PDF document text
    • http://peter-scherer.de/userfiles/file/82371361531.pdfIn PDF document text
    • https://fonixkoncert.hu/upload/file/32139762424.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_off0000d2c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2C4 10552 bytes
SHA-256: 1fc4c3d16cbacd0f4471b0a338bdec67cc1b3b0cd2a04fd3201b9a72c069dd69
font_01_sfnt_off0000eac9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC9 19528 bytes
SHA-256: 72319bdb794cf2231c5a95ecdb41898a3721570a7e59329e6959ee7882c38b32
font_02_sfnt_off00011d98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D98 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1