Malicious PDF — malware analysis report

Static analysis result for SHA-256 9850f81992ff041a…

MALICIOUS

PDF

94.4 KB Created: 2021-10-08 22:15:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 8546c9c251418f7c0696f836f3ff0719 SHA-1: 19b227a914cca358b77f5c56adfc049432f2f4a3 SHA-256: 9850f81992ff041ac35377f13636ae0f0a36596137cd4d211c30ea9ae9e62872
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many pointing to suspicious domains, and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic suggests it's part of a link farm designed to obscure the true destination. While no scripts were explicitly extracted, the presence of external URIs and the overall detection profile strongly suggest it's used for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://mama-light.net/business_school/uploads/file/63163310783.pdf In PDF document text
    • http://integrotech.pl/zdjecia/file/pupemovemokurotaboroxedav.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/ltmvk912nhq73kco1nqlonfr6t/xavakujojuxuvejemusama.pdfIn PDF document text
    • https://renhedc.com/uploads/files/202109081421057144.pdfIn PDF document text
    • https://vibanghanoi.com/uploads/files/gugeviliwurexibutabit.pdfIn PDF document text
    • http://www.asap-recruitment.net/upload/file/paboruzavixewulefun.pdfIn PDF document text
    • http://preprod.app-nomads.com/ugecam/admin/ckfinder/userfiles/files/50385709277.pdfIn PDF document text
    • http://ttmplus.com/userfiles/files/91089885355.pdfIn PDF document text
    • http://phfamilyrestaurant.com/uploads/files/27662079160.pdfIn PDF document text
    • http://pkynfe.net/userfiles/file/68917895606.pdfIn PDF document text
    • http://ryyw.com/upload/files/2021/09/202109131151562593.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/jivepegidokazuvisimomexez.pdfIn PDF document text
    • http://horizonpestservices.com/userfile/zivakubebatalikabaf.pdfIn PDF document text
    • https://tranthachcaodanang.thicongmaiche.com/uploads/image/files/76568633167.pdfIn PDF document text
    • http://murzilka.biz/images/uploads/file/rusobafovareku.pdfIn PDF document text
    • https://alrukn.co/userfiles/files/widodajififadereso.pdfIn PDF document text
    • https://heyratacademy.ir/file/dubipa.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614017d972dcc---puzunowepize.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/lupibukibojawakutujibo.pdfIn PDF document text
    • https://urbanshapes.in/userfiles/file/47341775360.pdfIn PDF document text
    • http://canadianrockies.info/files/file/vedax.pdfIn PDF document text
    • https://www.aaptuk.org/ckfinder/userfiles/files/26190396117.pdfIn PDF document text
    • http://batterseataxi.com/survey/userfiles/files/56376325909.pdfIn PDF document text
    • https://www.bevillelecomte.com/ckfinder/userfiles/files/fubipifipoboridifut.pdfIn PDF document text
    • http://orsini-blasioli.it/userfiles/files/bafadivimeze.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=mary%27s+perpetual+virginity+dogmaPDF 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_off00010746.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10746 20448 bytes
SHA-256: d1bf0776a58fa05ad3b8d7197d6c91d123bf1a1c4399bbed2411f72eb0005aec
font_01_sfnt_off00013b9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B9A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000153b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x153B1 11044 bytes
SHA-256: 7802f8b35eabff699cd18f6daf948af33a3c219b3bfca28d61ce84bd24df77ed