Malicious PDF — malware analysis report

Static analysis result for SHA-256 31a737a7ecbe2994…

MALICIOUS

PDF

82.6 KB Created: 2021-09-16 11:36:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b6c18588067c8f4e17485506a8b99bec SHA-1: be7c3d2c86bf57cfe346195bc657eddfc3839414 SHA-256: 31a737a7ecbe2994cc8df036c993823d1c741489c70440439bdb3119c261f806
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs pointing to external domains, many of which are structured as link farms or disposable hosting, suggesting a phishing or malware distribution scheme. The PDF's structure and embedded content indicate it's designed to redirect users to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://pistant.ru/uplcv?utm_term=how+to+take+pictures+at+night+with+android PDF link annotation
    • http://zhxndl.com/uploadfiles/files/poxolo.pdfIn PDF document text
    • https://siltri.com/fck_upload/file/razazavetu.pdfIn PDF document text
    • https://o2opr.co/userfiles/files/sogizivijoxakozaseviv.pdfIn PDF document text
    • http://yas-center.ru/userfiles/file/nurufovodusajezifi.pdfIn PDF document text
    • http://bbdecontra.com/userfiles/files/sabixi.pdfIn PDF document text
    • https://rallstarawards.us/nbloom/fckuploads/file/gananugixa.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d668029929---74440757536.pdfIn PDF document text
    • http://thangmayedex.com/webroot/img/files/wopekuxemuxu.pdfIn PDF document text
    • http://carneslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/22469467060.pdfIn PDF document text
    • https://zenit-npk.ru/files/file/7021957872.pdfIn PDF document text
    • https://aldurra.ly/images-editeur/img/file/tulujoson.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/5092640544.pdfIn PDF document text
    • https://5703n1n6999-6a55.com/contents/files/sagak.pdfIn PDF document text
    • http://www.elmundodelapiscina.com/ckfinder/userfiles/files/38717323663.pdfIn PDF document text
    • http://studioesflores.pl/obrazy/file/zazuwadajixozesapemob.pdfIn PDF document text
    • https://mklaassen.nl/images/file/88183720899.pdfIn PDF document text
    • http://harchovyk.com/userfiles/file/wiwinoxosijen.pdfIn PDF document text
    • https://noriupapildu.lt/ckfinder/userfiles/files/foguworavigimax.pdfIn PDF document text
    • https://szalkasszorutacskok.hu/app/webroot/files/content/files/4016159942.pdfIn PDF document text
    • https://ibliberia.com/ckfinder/userfiles/files/wesulesirawik.pdfIn PDF document text
    • https://fond.ru/userfiles/file/67812383477.pdfIn PDF document text
    • http://ingmontagna.com/userfiles/files/vixet.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/161355dac54c77---xutekokusotavevejuzovetur.pdfIn PDF document text
    • http://www.gonouvellezelande.com/files/detitirubusodixowi.pdfIn PDF document text
    • https://stop-remont.ru/ckfinder/userfiles/files/dinutidadowukame.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_off0000de19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f630.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF630 11016 bytes
SHA-256: b8499b4ee6c94aa08472ffc1357880a3e403f8cae78bbdc15e6602f500c75be9
font_02_sfnt_off00010f92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F92 17244 bytes
SHA-256: d6d27b724d0ddab49491e072ade7b86c986997e92b0adbc544716b5d304bcb5e