Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a809c0f38fec578…

MALICIOUS

PDF

82.5 KB Created: 2021-09-02 11:08:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e2c2e04308e0795b8eac899711a82731 SHA-1: 0e2bd55038ab37721f976c4bb1c68228e63f3e6e SHA-256: 1a809c0f38fec5787579b60d3a245378db597b684bbce77e941cff411bd10f1f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are sufficient to infer a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://crysiq.ru/uplcv?utm_term=compare+two+pdf+documents+for+plagiarism PDF link annotation
    • http://ersatzmonitor.de/userfiles/file/82111474621.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e13337fbcf---75657115147.pdfIn PDF document text
    • https://salwangurugram.com/files/jasixebebimajiwuwapuzezag.pdfIn PDF document text
    • http://german-ex.com/zenujofezofe.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/ruk2affg17k5pbshnh69n5ams7/46080383203.pdfIn PDF document text
    • http://2-view.org/home/view/public_html/ckfinder/userfiles/files/77504652248.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/kmpmq1uiudbs2fj7jnonjnraot/mizozujot.pdfIn PDF document text
    • http://woori-tour.kr/FileData/ckfinder/files/20210706_1B493EC1370DD208.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/6cc2e9ef2a08c8c3d7cb4079a073bc76/53588931071.pdfIn PDF document text
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/282c7f71e88a3c94cee82bbcb34996bd/fupapofiwefigetatuwom.pdfIn PDF document text
    • https://ev-owners.jp/userfiles//files/libanivefofova.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160982efd42095---ximozobolaboxuge.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/dapepelovemajaru.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/wudebomodubufipu.pdfIn PDF document text
    • http://wo-kop.pl/userfiles/file/25119744993.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f513217602---vidijagini.pdfIn PDF document text
    • http://xz-brand.com/ckfinder/userfiles/files/73205328421.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/hov1acp7r4e4h1qms6fdod3bil/81549834266.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_off0000db08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB08 11180 bytes
SHA-256: 57ff5a2d78598915b2bd7ebae845e9d437b6f2b49446c75b1eedef6699832bdb
font_01_sfnt_off0000f50e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF50E 17436 bytes
SHA-256: 126f658c7530cc6c713ee0b63a147c4c2ec781a537f559c881622ad638743628
font_02_sfnt_off00012217.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12217 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1