Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4721b3e96b0e2c1…

MALICIOUS

PDF

80.7 KB Created: 2021-09-18 06:00:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1f07b6d2e9a9ab8e78b5e5e32e38c684 SHA-1: cbc75ce02f691ff00ed704ff43967be76ab4d1ce SHA-256: d4721b3e96b0e2c1ae52e359643339de01b3adf046122a2197f351d6dd9acfdc
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to other PDF files hosted on various domains. Heuristics indicate this is a link farm on disposable hosting, with some links pointing to compromised CMS upload directories. ClamAV and ML classifiers strongly indicate maliciousness, likely for phishing or malware distribution via these linked documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://medvor.ru/uplcv?utm_term=polaris+jet+ski PDF link annotation
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613fda299b103---7027472504.pdfIn PDF document text
    • https://geneolock.com/ckfinder/userfiles/files/zopazirapubus.pdfIn PDF document text
    • http://lovelyspa.net/ckfinder/userfiles/files/56708341401.pdfIn PDF document text
    • https://sanidom.pl/img/file/kemulusekovusupate.pdfIn PDF document text
    • https://veaodaibrahma.com/uploads/image/files/jazegifigenapebuteb.pdfIn PDF document text
    • https://watfordfairtrade.org/app/webroot/img/files/55165032117.pdfIn PDF document text
    • http://ldksolar-officialliquidation.com/userfiles/files/sajowajeru.pdfIn PDF document text
    • http://distant-property.ru/fck_editor_files/files/goferejisafadidafujuv.pdfIn PDF document text
    • http://kleinschadenexperte.com/userfiles/file/62854175127.pdfIn PDF document text
    • http://hkwwta.org/userfiles/10457811367.pdfIn PDF document text
    • https://aimtronu.org/userfiles/file/vekoxefemomolosejosivefa.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/274d969f4dc0e6202f70fd05547ed896/68187981663.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613028346e20c---wisifewi.pdfIn PDF document text
    • https://viktorina.ledoritulys.lt/files/62162802781.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/29721487935.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16135987e2affd---naxexolunaxosewojolukes.pdfIn PDF document text
    • https://unaizahic.com/Files/files/75432982566.pdfIn PDF document text
    • http://christopherspubandgrille.com/userfiles/files/1960782057.pdfIn PDF document text
    • https://groupunsur2.com/contents/files/zubenilopanoxekowu.pdfIn PDF document text
    • http://loca-granderoue-montaletang.com/ckfinder/userfiles/files/28585438984.pdfIn PDF document text
    • https://xn--fct8ml6mwue.tw/uploads/files/supenerafuxinijili.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_off0000d724.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD724 18200 bytes
SHA-256: 8d6a7596fec1d7c278f8941879ab72d9b0fe409d24eb876c3ee02dd09ab57eb9
font_01_sfnt_off000106b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ecd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ECD 10220 bytes
SHA-256: ea179750eefb909c42ab3fa7ef167a10807c9ae65939038c63c7f95d678dd603