Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f4c9d4a4c50736d…

MALICIOUS

PDF

77.7 KB Created: 2021-09-01 20:54:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2a48e45498265f1e7c029cad31da1407 SHA-1: d215ac7cc9989deab5804facbec3a203a88b8676 SHA-256: 3f4c9d4a4c50736dbca79b39cb9e1afdda87dc2410937299d44785fac68cb3d7
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised websites and disposable hosting, suggesting it's part of a link farm designed to distribute further malware. The presence of PDF_RANDOM_URL_LINK and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics confirms the malicious nature of these links, which likely lead to the download of additional malicious files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://bangprice.combangprice.com/beta/cms_image/file/97297374747.pdf
    • http://movesearchesuk.com/userfiles/file/99914461511.pdf
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0259924f7a---wotupu.pdf
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/g5s8at6sl6ei6b0p7hp20r9vu0/zixesurepewujuk.pdf
    • https://elsa-daulte.com/ckfinder/userfiles/files/63724370337.pdf
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/bozijojeloluzerobumem.pdf
    • http://centrostudiapulia.it/files/files/72415531914.pdf
    • https://mokshadhamnepal.org/userfiles/files/jovipagixitemuxu.pdf
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160844d5ce08a4---56391812011.pdf
    • http://jingyitech.com/uploadfile/2183212604.pdf
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/9d05b79d10f641e8a273c7d359ccc4c7/dugibumovaselelixuxipun.pdf
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160bfbd3c94b3b---36530519829.pdf
    • https://componentcnc.hu/uploads/ckfinder/userfiles/files/71608861197.pdf
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/410c16dbb668c2831292a791189b759c/vagiwopo.pdf
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1611b870d08969---6057151631.pdf
    • http://dgjst.com/upfile/file/xifufasaliw.pdf
    • http://ambulatorioveterinarioilghirlandaio.it/userfiles/files/rugomo.pdf
    • http://tropo-design.com/ckfinder/userfiles/files/10114752695.pdf
    • http://zpb-maciejewski.pl/upload/fck/file/60663783002.pdf
    • http://eko-inwest.eu/upload/file/jotekedivivibuma.pdf
    • http://analogsys.com/uploaded/file/1156159528608abb4168fd2.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=how+is+a+mixture+different+from+a+pure+substance
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ca50.bin
c51b761b42e367042f9d7af65a34e89413f329bba8ae4f8b84423d26fb4ae6a9
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA50 16948 bytes
font_01_sfnt_off0000f53f.bin
3136eb2c7ab83e357130c932917299c67dfe39b24561b96301a7f76bbf2dc8dc
pdf-font-stream PDF embedded font (sfnt) at offset 0xF53F 11156 bytes
font_02_sfnt_off00010f28.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F28 16792 bytes