Malicious PDF — malware analysis report

Static analysis result for SHA-256 aac10a7352aa3467…

MALICIOUS

PDF

72.3 KB Created: 2021-09-10 13:57:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 276a6d9df71657d2aba248c3d51037ce SHA-1: 4bd647a9fc4bac3269d4089bd32b869d754ddb53 SHA-256: aac10a7352aa3467d81fc8ab53921a655e93bb8b0feecb65beefa6d302487d75
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to suspicious PDF files hosted on various domains, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and embedded URLs are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://krzeptowski.pl/file/lapojozuminavibadikogo.pdf In PDF document text
    • http://montpellier-business-plan.fr/mbp/upload/images/images/upload/ckfinder/luxifunu.pdfIn PDF document text
    • http://okmarin.ru/userfiles/file/41297437435.pdfIn PDF document text
    • https://soswzgierz.pl/web/uploads/files/gikunazimagakalisu.pdfIn PDF document text
    • https://responsible-tourism-alliance.com/content_file/files/11406056055.pdfIn PDF document text
    • https://uroci-kursove.com/userfiles/file/buzupudeso.pdfIn PDF document text
    • http://xn--o39a91gvwm83kbsn.com/FileData/ckfinder/files/20210905_5595562535C1B0A9.pdfIn PDF document text
    • http://banner-ever.com/ckImg/files/miboka.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/161399110a81ca---74723011152.pdfIn PDF document text
    • http://doorsatyrau.com/ckfinder/userfiles/files/65537899646.pdfIn PDF document text
    • http://www.luna1956.com/images/library/File/xeraboduwufifudexizi.pdfIn PDF document text
    • http://tries.cz/media/images/upload/file/47107262554.pdfIn PDF document text
    • http://easternhoteljeju.com/FileData/ckfinder/files/20210904_7DE6188F522A62FE.pdfIn PDF document text
    • http://ebbers-schilderwerken.nl/uploads/files/73547451425.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/fijowekiloxinoxake.pdfIn PDF document text
    • https://ratodua.com/contents/files/68582813530.pdfIn PDF document text
    • http://fruhmann-elektrotechnik.at/tuvibemim.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/e78tu7kpsbm0fh5qn8cgu49qq1/dowevowusowavozuwusaga.pdfIn PDF document text
    • http://loscogliodifavignana.it/userfiles/files/mexatisuwo.pdfIn PDF document text
    • http://hrampetraipavlavosstanovlenie.ru/content/images/user/file/vizizudoxelolemojuri.pdfIn PDF document text
    • https://adasms.fr/userfiles/file/budogi.pdfIn PDF document text
    • https://www.adom.biz.pl/ckfinder/userfiles/files/83564084203.pdfIn PDF document text
    • https://psychotherapie-coeppicus.ch/upload/file/suxolazujanurisup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=no+equalizer+spotify+androidPDF 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_off0000b810.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB810 16540 bytes
SHA-256: df35519470406b9dea3e95255fc665b53959ba218b464002ab9d6bd70cba2a6a
font_01_sfnt_off0000e27c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE27C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fa93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA93 10888 bytes
SHA-256: da88904a14978704008d6f4b37e946e5bea14af59c8d569fee88c50ea6de956d