Malicious PDF — malware analysis report

Static analysis result for SHA-256 7678781c348840fe…

MALICIOUS

PDF

77.2 KB Created: 2021-06-16 05:38:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 3fa4f21769a9d2c343cce53152530937 SHA-1: df0f7e50ab76f7e1d1f9b757abaa64f4a8300e5e SHA-256: 7678781c348840fedb18930fe6f89c39c11b9856211de03d01d0c5ec6e710141
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://catamma.ru/uplcv?utm_term=zombie+gunship+survival+mod+apk+unlimited+all PDF link annotation
    • http://dobrasekacka.cz/userfiles/file/85195308821.pdfIn PDF document text
    • https://bd-sokolovska.eu/userfiles/file/92642622212.pdfIn PDF document text
    • http://urbanconstructions.org/images/uploadedimages/file/41620400179.pdfIn PDF document text
    • https://chpcentre.com/files/file/5260072089.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1dadaacc1---duvifozekud.pdfIn PDF document text
    • https://castel.ro/userfiles/file/41790773990.pdfIn PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607749e66f95e---lixokedaj.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16083289b5a829---55794294090.pdfIn PDF document text
    • http://pogotowienaukowe.com/Upload/file/65849536133.pdfIn PDF document text
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/1033d4e803d37560030596d0125ad778/11635588470.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/a54dd51a284c522a7cc31b6fa3a949ee/tilajigatavi.pdfIn PDF document text
    • http://jgbt.us/pds/userfiles/files/filurozolenuvedapibokagiw.pdfIn PDF document text
    • http://tropo-design.com/ckfinder/userfiles/files/29313574208.pdfIn PDF document text
    • http://parfumerieindex.nl/images/uploads/raduva.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/uoj3kd7sd03r7u4vp1f1fp3e81/37826640071.pdfIn PDF document text
    • http://nguyenquangcomputer.com/upload/ck/files/54857490414.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE9D 5596 bytes
SHA-256: 781d5ba053b783aef232419226d7f7a8c5ce01ecdbbfc332af940038456be8b3
font_01_sfnt_off0001017e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1017E 11224 bytes
SHA-256: 8fd989a7d88a3ea6fd2b8931cfb24f5e87febcc03435f3896d635b5d879ea3ed