Malicious PDF — malware analysis report

Static analysis result for SHA-256 55caa9d67aba1eea…

MALICIOUS

PDF

80.6 KB Created: 2021-09-17 23:41:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 03b45d8877c53d8d1c66a891cadb0113 SHA-1: e34111535a8ab17bb6e23134e7e12e627017817b SHA-256: 55caa9d67aba1eea6ca793bfccbda9c54f22ace9911d3175e8ce6c1fe45dbca3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable domains and are structured as a link farm, indicating a malicious intent to redirect users. The ML classifier and ClamAV detection strongly suggest this PDF is malicious, likely a phishing or malware distribution lure. Although no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://bikipvuikhoedep.com/app/webroot/files/editor_upload/files/96798751862.pdf In PDF document text
    • http://doingthing.com/downloads/blog/geust/files/ritujerenefifakejo.pdfIn PDF document text
    • https://bharatiyabhashaparishad.org/ckfinder/userfiles/files/nigewutolixexa.pdfIn PDF document text
    • http://siripanyalamphun.com/user_img/files/51418566198.pdfIn PDF document text
    • http://studiocalderini.it/userfiles/files/tukitoboxolilufel.pdfIn PDF document text
    • https://iuoshili.com/upload/users/files/56924582650.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16132dad0b0deb---57543286655.pdfIn PDF document text
    • http://studiozammuner.eu/userfiles/files/93753340799.pdfIn PDF document text
    • http://bycongroup.com/UserFiles/file/29956856064.pdfIn PDF document text
    • https://gabinetpro.pl/kosmetyczka/krakow/files/xizitinaxizeniwefi.pdfIn PDF document text
    • http://cascinamana.it/userfiles/file/zifupejikabivonavewijob.pdfIn PDF document text
    • http://hondasushi.com/uploads/files/3434984591.pdfIn PDF document text
    • http://xhiehchin.com/Xhieh_News/_file/95930376751.pdfIn PDF document text
    • http://oletrans.sk/editor_uploads/files/livebukiwizajefatum.pdfIn PDF document text
    • http://technestudio.eu/userfiles/files/75951823010.pdfIn PDF document text
    • https://cfacgroup.com/uploads/FCK_files/file/niparonujozukodiwimam.pdfIn PDF document text
    • https://ewt.cz/res/file/lojosotularijomesonoj.pdfIn PDF document text
    • https://armature.ir/cache/fck_files/file/4923697575.pdfIn PDF document text
    • http://fishtech.org/uploads/userfiles/file/file/lozug.pdfIn PDF document text
    • https://aviseco.ro/userfiles/file/58832094534.pdfIn PDF document text
    • https://nisahanpin.com/calisma2/files/uploads/84148691404.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/39363345992.pdfIn PDF document text
    • https://gemwares.com/userfiles/file/supupazekudapoj.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/44992738026.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=gta+5+cheats+xbox+one+phone+dirt+bikePDF 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_off0000d43b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD43B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC52 11072 bytes
SHA-256: 20e22bf9c96f0b8a0f8a77e885bf7e3f8be9391c81b546023f975940871b2f0e
font_02_sfnt_off000105f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105F2 18484 bytes
SHA-256: 9739c938f95dba54823b26b448fefc49f3e30a016ea1c1b39e0a69fb114ba53a