Malicious PDF — malware analysis report

Static analysis result for SHA-256 f261eb3b3712c4b0…

MALICIOUS

PDF

74.5 KB Created: 2021-09-24 21:09:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 072a879459fe48f4adfd79c33e4fa790 SHA-1: 96c0216fb5319c8fed989da662221cdbb5f7fc58 SHA-256: f261eb3b3712c4b0806eb3027dfa01bb4520ee7edfd21cd893e482d38e653f39
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, with many pointing to unknown or potentially malicious domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the link farm characteristic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://szjwwj.com/userfiles/file///wajituxe.pdf In PDF document text
    • https://derfo.info/resimler/files/vibotopunu.pdfIn PDF document text
    • http://www.horakgolf.cz/ckfinder/userfiles/files/barovefijewofirotemibu.pdfIn PDF document text
    • https://www.tri-or.fr/tri-or/ckfinder/userfilesfiles/gesowugovek.pdfIn PDF document text
    • https://euroquimicadistribucion.com/zabaleta/data/imagenes_contenidos/file/nizoga.pdfIn PDF document text
    • http://selidbe-beograd.info/files/11297491850.pdfIn PDF document text
    • https://locktactyuma.com/userfiles/file/80798318191.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-9-16/20210916072902415020.pdfIn PDF document text
    • https://maturana.cl/upload/file/mopezezuximuka.pdfIn PDF document text
    • http://a-daily.jp/app/webroot/contents_img/files/19676983740.pdfIn PDF document text
    • https://delaneyllc.com/ckfinder/userfiles/files/lotodisawinimixomog.pdfIn PDF document text
    • http://unibox.lv/files/text/39733925130.pdfIn PDF document text
    • https://dcicz.org/userfiles/file/35132550027.pdfIn PDF document text
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/4e9dc3fe2d67914b557c7c871224f155/fefomumususijepebimigat.pdfIn PDF document text
    • http://bsa.by/ckfinder/userfiles/files/6867268822.pdfIn PDF document text
    • https://www.db-ynox.fr/ckfinder/userfiles/files/38683048065.pdfIn PDF document text
    • http://bandenplaats.nl/cmsimages/file/bizuxunu.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/mijuvuxivukovokurigixeri.pdfIn PDF document text
    • http://reszke.pl/fckeditor/editor/filemanager/connectors/php/file/46909631378.pdfIn PDF document text
    • http://peoplefineart.com/assets/202109/files/20210919140754904894.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/wademutagur.pdfIn PDF document text
    • http://autodilygood.cz/files/file/80862156470.pdfIn PDF document text
    • https://hazeloyun.com/calisma2/files/uploads/71184075052.pdfIn PDF document text
    • http://desiaussies.com/ckeditor/uploads/files/dakexone.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=winner+soccer+evo+elite+play+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_off0000b868.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB868 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d07f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD07F 10540 bytes
SHA-256: 657f9ce3bad210b39ade84c5d59154c7326d9634ff6f0a061b66dafedc553bd9
font_02_sfnt_off0000e8b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B2 19276 bytes
SHA-256: 9c2042c46a258cc98dfe91bcfd0bafa4f8a6bbd4e5f6babb97225b640674f0c6