Malicious PDF — malware analysis report

Static analysis result for SHA-256 66fda7632439c2b8…

MALICIOUS

PDF

78.3 KB Created: 2021-07-27 05:45:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 6b4592d55762a85b1103462166614a5b SHA-1: c51ed43a3cd3be22f5e984b5c103bb2a01f27fd8 SHA-256: 66fda7632439c2b87380c70b32532125372a0de0d7ba399a8de1c71ff8ebed6d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to various websites, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using such sites to host PDF files, likely for SEO poisoning or to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • 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 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://lexcochoralsoc.org/demo/lccs/beta/userfiles/files/91782861380.pdf In PDF document text
    • http://laweasy.kr/userfiles/file/xagef.pdfIn PDF document text
    • https://windsbs.biz/files/file/60721549231.pdfIn PDF document text
    • http://libertyquad72.fr/userfiles/file/55204264251.pdfIn PDF document text
    • https://bjjewels.net/nbloom/fckuploads/file/51801271007.pdfIn PDF document text
    • https://www.alapan.org/fckimages/file/10337349557.pdfIn PDF document text
    • http://btfa.tw/upload/files/41167509619.pdfIn PDF document text
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/82f597710346174dca893f28578521b1/devarosemuperiwowopejek.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ccb59b44c2---36028348655.pdfIn PDF document text
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/of8jeu703l9d7vmn2o07cf3rk5/71878499500.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/68b610a4e9c30bc5482a527936cea0da/xuwalawup.pdfIn PDF document text
    • http://stsaischoolamritsar.com/slbdavbatala/userfiles/file/67155198887.pdfIn PDF document text
    • https://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/6ce325f4b3dbe896e22716d74db55721/kofufexunimuli.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e98180b28e---49810987033.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/26731162253.pdfIn PDF document text
    • https://aljazeerahdrilling.com/userfiles/files/45483461732.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160d8e53d69cfe---gomanefevaregokawinidugiz.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/74a65adlp8r23t8l9su0m5clf0/20522207702.pdfIn PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/nobizuwobafew.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/1607b267cd2f7c---64097482723.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/cd250bbc42154dfe186c9f1d1a9a0d79/dusesuzujafuremotet.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a757a04f672---waxaxor.pdfIn PDF document text
    • https://atpl.aero/ckfinder/userfiles/files/11342488707.pdfIn PDF document text
    • https://www.barrau-philippe-sedeco.fr/ckfinder/userfiles/files/44819117428.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=resonancia+qu%C3%ADmica+org%C3%A1nica+ejercicios+resueltosPDF 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_off0000caf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAF8 16984 bytes
SHA-256: 39966ceac27d9f562151ef41d5ddc6e4074cddf088252de86981937511111c87
font_01_sfnt_off0000f602.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF602 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010e19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E19 11236 bytes
SHA-256: 6896f7800727803d874b3711eb08243e39fd5447c166396e8808283bac69d404