Malicious PDF — malware analysis report

Static analysis result for SHA-256 729bded2556e8e4d…

MALICIOUS

PDF

70.2 KB Created: 2021-09-18 01:26:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2a996aa2e14afacc5866b20ddaaa154f SHA-1: 02adbff659bc0698207151558fcc468c3019703c SHA-256: 729bded2556e8e4d84b5d7a48ca5c38c3a556cab41d1638f538f2f82f8a89fbb
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file identified as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, many of which point to disposable hosting and appear to be part of a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests a malicious intent, likely to lure users to phishing sites or download further malware. While no scripts were explicitly extracted, the nature of the PDF and its numerous external links indicate a phishing or malware distribution vector, aligning with Spearphishing Attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://catamma.ru/uplcv?utm_term=free+fire+config+maker+apk PDF link annotation
    • http://asustainable.com/global/file/17341672367.pdfIn PDF document text
    • http://bephoangdung.vn/uploads/ckfinder/files/xaxejunosefarabexof.pdfIn PDF document text
    • https://cylinder96.ru/admin/ckfinder/userfiles/files/pagudevojev.pdfIn PDF document text
    • https://xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/pupezogiwapuxajiwojataf.pdfIn PDF document text
    • http://jpind.pl/userfiles/file/sunanul.pdfIn PDF document text
    • http://blueview.nl/app/webroot/files/userfiles/files/10878706807.pdfIn PDF document text
    • https://careerroots.net/ckfinder/userfiles/files/76382566791.pdfIn PDF document text
    • http://ediliziaunoaventi.com/userfiles/files/vutazinumuzonututol.pdfIn PDF document text
    • https://lanna-flyingclub.com/ckfinder/userfiles/files/79559782331.pdfIn PDF document text
    • http://blekinge.boj.se/uploads/userfiles/files/49435460793.pdfIn PDF document text
    • https://www.drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161348bb789668---35628273580.pdfIn PDF document text
    • http://www.synagoge-stommeln.de/ckfinder/userfiles/files/getekisimekezeloni.pdfIn PDF document text
    • https://ontech.vn/images/ckeditor/files/35432879351.pdfIn PDF document text
    • http://www.lasallelille.com/admin/ckfinder/userfiles/files/zexafajul.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff5b79ece9---lasikogi.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/45723793019.pdfIn PDF document text
    • https://autosaloncenter.com/uploads/file/tatafuzu.pdfIn PDF document text
    • https://mami-m.com/Uploads/userfiles/files/wobetowetulatesizowel.pdfIn PDF document text
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/885373271.pdfIn PDF document text
    • http://ghettaetamionarchitetti.it/userfiles/files/xejisujeromorovidi.pdfIn PDF document text
    • https://posh.hr/files/86388156627.pdfIn PDF document text
    • http://nemdanangpho.com/uploads/2021-09-18/images/files/36153477858.pdfIn PDF document text
    • http://giovanninociti.com/userfiles/files/53197495864.pdfIn PDF document text
    • http://zit-tech.com/userfiles/files/62806762210.pdfIn PDF document text
    • http://adfaveo.com/image/files/20210917_162809.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_off0000b386.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB386 15528 bytes
SHA-256: 2979baacb91f4bb1474f50d4e63cef71c6925f973c678f84e09e9556bd4722ea
font_01_sfnt_off0000daf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f307.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF307 10580 bytes
SHA-256: 052228683dab26f4c0ef381838ba444bf7b44bbe3967652753acd1b331bfdcc0