Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5de8a1880d66cd1…

MALICIOUS

PDF

78.7 KB Created: 2021-09-16 03:37:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4d85df8ec4adafcce74be435ac945866 SHA-1: e400ab4cb656af85350a969488b5185d8cbbcdbb SHA-256: b5de8a1880d66cd115d1f3d6443c1351929aa9408620dc537afaef2f345c49a3
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and is identified as a link farm pointing to compromised WordPress upload storage and other disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware sites. The embedded JavaScript is likely used to facilitate these redirects or potentially execute further malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://smalternatywa.pl/media/upload/files/be17220ae487f88b5614957616e2a80f.pdf In PDF document text
    • http://afro-safari.com/upload/files/mijutekopoz.pdfIn PDF document text
    • http://avon-bratislava.sk/files/files/veligujali.pdfIn PDF document text
    • http://zjgjqmr.com/v15/Upload/file/202193858115302.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/461f94780dac3adfdb574bab99b035ee/19356410156.pdfIn PDF document text
    • http://www.hzkontejnery.cz/ckfinder/userfiles/files/sunakoximaxevuw.pdfIn PDF document text
    • http://psycare-spb.com/userfiles/file/jurepupilajuviraropun.pdfIn PDF document text
    • https://dolupin.com/calisma2/files/uploads/bexotufedigoviwede.pdfIn PDF document text
    • https://esprimagroup.com/userfiles/file/movotapelelo.pdfIn PDF document text
    • https://svingenieria.cl/userfiles/file/3811260756.pdfIn PDF document text
    • http://sfalojistik.com/userfiles/file/xamorurom.pdfIn PDF document text
    • http://xn--3bsx3iw22bmot.com/filespath/files/20210909175748.pdfIn PDF document text
    • https://www.marjojaspers.nl/ckfinder/userfiles/files/matavupipokajelevitur.pdfIn PDF document text
    • http://1night2day.com/ckupload/files/loxavivigetefibi.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/161428889ef101---26958521111.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/c58676717bd45c59a5c137b978067fde/loxibedulovub.pdfIn PDF document text
    • http://akiyastyle.com/app/webroot/js/ckfinder/userfiles/files/nadanafo.pdfIn PDF document text
    • http://na-bytecek.cz/UserFiles/File/39156535122.pdfIn PDF document text
    • https://sgcaregiver.org/contents/files/dedinefufirel.pdfIn PDF document text
    • https://cs168.tw/upfiles/editor/files/86900845828.pdfIn PDF document text
    • https://afayl.com/userfiles/file/lagumagelodexewizudu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=paw+patrol+movie+stream+onlinePDF link annotation
    • 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_off0000d186.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD186 17188 bytes
SHA-256: 73a2118289ea5646ad5a60773a202f596fe9b774ad4a942a38c97ea6cdb91502
font_01_sfnt_off0000fd75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD75 10568 bytes
SHA-256: efcb20bbafef6c7c142a55505e2f4c222e8be98492bd7be0d2e51de97da434f5
font_02_sfnt_off000115a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1