Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4b1de85804f9632…

MALICIOUS

PDF

74.3 KB Created: 2021-09-26 06:21:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 648fc05649656f7acea13f8e9c5b15a3 SHA-1: 42d6ebeaceaa00e4e598cacfa1e8f2aad30eeb3a SHA-256: f4b1de85804f963239d13fad124162ed08baf076a4586e1deeecc71f53b5544d
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating it is a link farm hosted on disposable domains, designed to redirect users to other malicious PDFs. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded URLs point to suspicious domains and IP addresses, indicating a probable attempt to download further malicious content or redirect to phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://smidgel.ru/uplcv?utm_term=avengers+play+store PDF link annotation
    • https://iwanbim.com/userfiles/files/femusifuli.pdfIn PDF document text
    • http://xn--o39a91gvwm83kbsn.net/FileData/ckfinder/files/20210913_AC7B80172574F77F.pdfIn PDF document text
    • http://www.bluefashion.cz/ckfinder/userfiles/files/71185465650.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614b1da5d5873---93807180065.pdfIn PDF document text
    • http://slovbau.sk/test/userfiles/file/7448047688.pdfIn PDF document text
    • http://osteriadelcampanile.com/userfiles/files/viwamaxezategefasana.pdfIn PDF document text
    • http://hiroi-es.info/yamituki-n/uploads/files/23292509391.pdfIn PDF document text
    • https://laatuwhuisweerstralen.nl/upload/file/lezawuf.pdfIn PDF document text
    • http://mindentudor.hu/userfiles/file/feruxatepudosebejomabukex.pdfIn PDF document text
    • http://thaimassagemodel.com/ckfinder/userfiles/files/93136342054.pdfIn PDF document text
    • http://thuannam.com/image/files/20348420905.pdfIn PDF document text
    • https://kamhosting.nl/ckfinder/userfiles/files/xiganenud.pdfIn PDF document text
    • http://mobilahomedesign.com/userfiles/files/27211800458.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/vekaxojanemesorin.pdfIn PDF document text
    • https://gangnampools.com/contents/files/77748866914.pdfIn PDF document text
    • http://knx-shop.ru/admin/ckfinder/userfiles/files/91868763522.pdfIn PDF document text
    • http://caopump.com/admin/userfiles/file/21852489247.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/30481875439.pdfIn PDF document text
    • http://farmaciafici.com/userfiles/files/pidimizifogumuginudizo.pdfIn PDF document text
    • http://noithatdangcap.vn/app/webroot/uploads/files/zakigepes.pdfIn PDF document text
    • http://178.62.148.222:300/ckeditor/ckfinder/userfiles/files/jikuzekawunajedolopu.pdfPDF link annotation
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132710d2833f---42900736081.pdfIn PDF document text
    • http://studioambienteterritorio.it/userfiles/files/10997340707.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_off0000b835.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB835 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d04c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD04C 10496 bytes
SHA-256: f1622c1ddcd224e7a9aa4101ea568383488d1b1bf48a83e28cd43f63d1f02e2f
font_02_sfnt_off0000e861.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE861 20236 bytes
SHA-256: c4f5aa4e52598a9223d0ae49efdf86d4542812ae1cf4932f9458722ea9d4bc29