Malicious PDF — malware analysis report

Static analysis result for SHA-256 28fa512126ec41d3…

MALICIOUS

PDF

80.0 KB Created: 2021-09-15 09:25:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 322d287949dd843c2ab04a55a9442c45 SHA-1: 72d9f02278d3c6d230354c859277c6c79fc5a294 SHA-256: 28fa512126ec41d36cd078b377754762562dfbc1bc6cdefb73984a8f6b4df4c2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The PDF contains numerous links to disposable domains, indicating a link farm designed to obscure the ultimate destination. While no scripts were directly extracted, the PDF structure and heuristic firings strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://humidorio.de/ckfinder/userfiles/files/mitebazotufaxusezijiwifem.pdf In PDF document text
    • http://prestinoequitacion.com/imagenes/upload/files/1292521131.pdfIn PDF document text
    • http://bergepkolcsonzo.hu/userfiles/file/34839611807.pdfIn PDF document text
    • http://studiotecnicobonoli.com/userfiles/files/wokukeromagupamepoli.pdfIn PDF document text
    • http://sumosushingrill.com/uploads/files/rixogogezosokitafin.pdfIn PDF document text
    • http://5mal4.de/moneyvidya/web/images/userfiles/file/1363987481.pdfIn PDF document text
    • http://tageedesign.com/ssmpt/documents/file/detit.pdfIn PDF document text
    • https://juniorclublivorno.com/sitonews/images_upload/files/webawusenoxubibewopakebaw.pdfIn PDF document text
    • http://elfuklid.cz/foto/Image/file/10000663874.pdfIn PDF document text
    • https://studioconcept-stand.com/fck_userfiles/file/xivizudokabebasew.pdfIn PDF document text
    • http://shuimotongyuan.com/userfiles/file/11718203779.pdfIn PDF document text
    • http://compsult.net/userfiles/file/witojevosawuzipamisamalu.pdfIn PDF document text
    • http://frutapac.com/ckfinder/userfiles/files/79605841408.pdfIn PDF document text
    • http://ueros.fr/admin/ckfinder/userfiles/files/xorawarulixosul.pdfIn PDF document text
    • https://cpsguffanti.it/uploads/file/41026698525.pdfIn PDF document text
    • http://www.onlinenieuwsbriefversturen.nl/gebruikers/afbeeldingen/zaken.pdfIn PDF document text
    • http://jpind.pl/userfiles/file/86748246063.pdfIn PDF document text
    • http://zima.italie-ubytovani.cz/data/file/41107043211.pdfIn PDF document text
    • http://naturalmis.com/userfiles/file/wirajupajovepubuzu.pdfIn PDF document text
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/04ca5d76a9b01a71cf62bfc5309143fc/27238514031.pdfIn PDF document text
    • http://creatinglifeoptions.com/userfiles/files/vusofedevi.pdfIn PDF document text
    • http://oris-am.com/editor_up/biligegoxufopujakiza.pdfIn PDF document text
    • http://hzeiger.com/userfiles/file/vebekokedobufolije.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c9f4ea36c2---gejebixejeb.pdfIn PDF document text
    • https://cakesandcupcakes.net/userfiles/files/vadurisosikut.pdfIn PDF document text
    • http://tuttotop.com/userfiles/files/gufixagitexega.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=live+talk+hack+apkPDF 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_off0000d28c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD28C 18296 bytes
SHA-256: 56864932c6f207c0224bcc7ef85c4aad441c1fe7b65119578e371017dfd01fd8
font_01_sfnt_off000101fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101FB 10092 bytes
SHA-256: 368552f707adef466dc08e79584f79d109a9696d3fc2525c6b1e3e7bf924a8fa
font_02_sfnt_off000118a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1