Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9b41a198cf3c801…

MALICIOUS

PDF

82.1 KB Created: 2021-09-22 20:37:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 81a60e566cd07015f4be82148e96d6b2 SHA-1: 52b1ef474dce0b57f391db9004f102015b155219 SHA-256: b9b41a198cf3c801d317daefb981a04956ed59b4aca2a4738fcf744eca36e51e
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable domains. Heuristics indicate this is a link farm designed to redirect users, and a specific heuristic flags it as an MFA/one-time-code harvesting lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to phish credentials or deliver a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=samsung+galaxy+s+i9000+games PDF link annotation
    • https://appvid.eus/userfiles/files/zipevanixikerenadepunaso.pdfIn PDF document text
    • https://okinawa4d.com/contents/files/gukosoridu.pdfIn PDF document text
    • http://docando.es/js/ckfinder/userfiles/files/xudusuzimuzifaweludon.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613690b925daa---xidujeminadepoletamav.pdfIn PDF document text
    • http://bangiyaparishadtoronto.ca/bpt/editor/uploadfiles/kumalesaxesavanokirog.pdfIn PDF document text
    • https://postelezmasivu-praha.cz/ckfinder/userfiles/files/gijowofevobabibuvosuvilos.pdfIn PDF document text
    • https://commonlawhouse.in/userfiles/file/69047306094.pdfIn PDF document text
    • http://tg-focus.ru/userfiles/files/6104341703.pdfIn PDF document text
    • http://burningspearmarketplace.com/js/ckfinder/userfiles/files/83320230346.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/35e61916d6c851140d38138ae4ff4fe4/muvofubapolase.pdfIn PDF document text
    • http://amghanoi.com/images/ckeditor/files/lulaxopikikuve.pdfIn PDF document text
    • http://xn--c1aejbdnke.xn--p1ai/admin/ckfinder/userfiles/files/juvubalazivan.pdfIn PDF document text
    • http://graphicyazd.com/ckfinder/userfiles/files/41933442704.pdfIn PDF document text
    • http://nfc-lampang.com/user_img/files/65352673498.pdfIn PDF document text
    • http://usagimatur.com/files/others/59286438296.pdfIn PDF document text
    • https://mancomunidadvaldizarbe.com/userfiles/files/12812044222.pdfIn PDF document text
    • https://abss.pt/userfiles/file/bunemazudikivafore.pdfIn PDF document text
    • http://xy-interior.com/uploads/files/202109032257142203.pdfIn PDF document text
    • http://hunicorn.hu/userfiles/file/taxotobedatuwer.pdfIn PDF document text
    • https://zweefvlieg.net/userfiles/file/52297116837.pdfIn PDF document text
    • https://jamurgoreng.net/contents/files/zusanifepafaxiwew.pdfIn PDF document text
    • http://bradhelferlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/valoxutodebidaweb.pdfIn PDF document text
    • http://nbc.com.vn/ckfinder/userfiles/files/tafovipulir.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_off0000d9bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9BB 18600 bytes
SHA-256: af3c6565fe318c62dcccfe4a20c690db9370960e7193ea3e944336605d53a0ee
font_01_sfnt_off000109c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109C7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000121de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121DE 10816 bytes
SHA-256: 012dfc2f4dbd1faa1ea5d8b1167f5cd0fc8f0fbd94675dce220e75d8947bbbc9