Malicious PDF — malware analysis report

Static analysis result for SHA-256 9ea6c7557f25982c…

MALICIOUS

PDF

82.4 KB Created: 2021-09-15 16:09:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 477526790759a414d58fb2079357d954 SHA-1: 8ee979cf52d308612c5af5cb5b245670c761ffa1 SHA-256: 9ea6c7557f25982cb9ab253a57f0ba6737ac66d85d87d4420fadd0156d8ce0ab
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URLs, many of which are part of a link farm, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of embedded URLs and the heuristic PDF_SEO_DISPOSABLE_LINK_FARM rule point towards a campaign designed to redirect users to potentially harmful sites, masquerading as a system update.

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 https://crewmak.ru/uplcv?utm_term=system+app+updater+xiaomi PDF link annotation
    • https://clubkdo.fr/img/pics/files/sefali.pdfIn PDF document text
    • https://myparrotfood.com/user_files/files/fosebunonupeso.pdfIn PDF document text
    • http://betonkeritesek.eu/Content/files/mevanuxegulonupowe.pdfIn PDF document text
    • http://cancunday.com/travela/img/files/jepukij.pdfIn PDF document text
    • http://poetische-malerei.de/web/editor/files/jezipikibozorusewobom.pdfIn PDF document text
    • http://agrion.org/upload/fichier/reritemodatisidewuvoza.pdfIn PDF document text
    • https://etonbio.com/newsLetters/images/file/sirunaleferojofovalu.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c5be8aa68c---76475560779.pdfIn PDF document text
    • http://medicaldistri.com/ckfinder_files/files/tunejuxidemupewame.pdfIn PDF document text
    • http://capitolmetrophysicaltherapy.com/userfiles/file/26161990451.pdfIn PDF document text
    • http://cpbnatation.fr/fckeditor/userfiles/file/ratamupimeladebijaga.pdfIn PDF document text
    • http://detaycopymatbaa.com/userfiles/file/58602134660.pdfIn PDF document text
    • http://minhtoangalaxyhotel.vn/app/webroot/files/ckfinder/files/wevuvupeb.pdfIn PDF document text
    • https://repetitorebi.ge/userfiles/files/72808701929.pdfIn PDF document text
    • https://indirimlipin.com/calisma2/files/uploads/sijiwodolekoretowegumosi.pdfIn PDF document text
    • http://vasekurzy.cz/userfiles/file/rujobemivabajuxegajefigo.pdfIn PDF document text
    • http://hyunshin.net/userfiles/file/39676671247.pdfIn PDF document text
    • http://uforoi.com/app/webroot/uploads/files/29087238013.pdfIn PDF document text
    • http://medizator.ru/ckfinder/userfiles/files/71296500124.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/d794p3u53uq3005cl4grdv6i92/27026753341.pdfIn PDF document text
    • https://szelvedojavitasmiskolc.hu/files/files/61013700015.pdfIn PDF document text
    • http://v-lukomorie.com/uploader/files/nirugeporadaduxoguvut.pdfIn PDF document text
    • http://ferramentabelleggia.it/public/file/veguxe.pdfIn PDF document text
    • https://flardochform.se/userfiles/file/zoguz.pdfIn PDF document text
    • https://happy-playground.gr/uploads/_uploads/files/1133013668.pdfIn PDF document text
    • http://crc.creativechange.net/ckfinder/userfiles/files/zorugivizabebuxatuta.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_off0000db52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB52 18504 bytes
SHA-256: ad76100b39413269d6d747b32c4b09abdcfcdd233ba5594f693554a0348cb99d
font_01_sfnt_off00010acc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ACC 10796 bytes
SHA-256: ae63de42490576ee63ba33af7e5f70fc46e6fac5a38f91487f69938a4ce26590
font_02_sfnt_off000123bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1