Malicious PDF — malware analysis report

Static analysis result for SHA-256 536d20479190c270…

MALICIOUS

PDF

79.8 KB Created: 2021-09-18 23:48:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4bbebbfcdfde6a29e3a97344e1d22257 SHA-1: d3c0bd67849e4066a7b73b0188b05c5355e1ee2f SHA-256: 536d20479190c2707cc3c69d4c3ea2e455042ae7564008258e41cff379cd7707
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically identified as a phishing or trojan threat. Heuristics indicate it functions as a link farm, directing users to multiple distinct hosts, some of which are hosted on compromised CMS uploads. The embedded URLs, such as http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16143cedbb3ad1---57942877161.pdf and https://cgeminfos.ma/upload/file/marunop.pdf, are likely part of this malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cgeminfos.ma/upload/file/marunop.pdf In PDF document text
    • http://inarchengineering.it/userfiles/files/towawakavaxexoxumuja.pdfIn PDF document text
    • https://everestart.com/images/stories/file/77973646602.pdfIn PDF document text
    • http://expertcomptablecourreges.fr/michel_courreges/userfiles/file/zifinapuluwexadex.pdfIn PDF document text
    • https://sibservis.com/ckfinder/userfiles/files/22007328606.pdfIn PDF document text
    • http://bobhendrix-law.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tijawejuruzeza.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/b98fa5ede468fd11e4ad67534700cf3b/kogupak.pdfIn PDF document text
    • http://z500.si/files/49578631495.pdfIn PDF document text
    • https://am-system.eu/ckfinder/userfiles/files/7492592647.pdfIn PDF document text
    • https://bocion.com/ckfinder/userfiles/files/48232791667.pdfIn PDF document text
    • https://cosplay-expo.it/ckfinder/userfiles/files/98704230511.pdfIn PDF document text
    • https://santa.my/images/users/00000000/files/duxuzovojomu.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16143cedbb3ad1---57942877161.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109181950447831.pdfIn PDF document text
    • http://tai-group.com/upload/files/16378272769.pdfIn PDF document text
    • https://unaizahic.com/Files/files/weridasifupit.pdfIn PDF document text
    • https://pisangmanis.com/contents/files/79955976374.pdfIn PDF document text
    • https://aljazeerahdrilling.com/userfiles/files/98300847074.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136635b06aa3---xokipawopipukupopazidej.pdfIn PDF document text
    • http://sdes.in/uploads/17634914002.pdfIn PDF document text
    • https://bi-kiesabbau.de/cmsimple/images/file/46843754309.pdfIn PDF document text
    • http://longarmacademy.net/fckeditor/userfiles/file/fodiruxufoda.pdfIn PDF document text
    • https://jv-cms.crazy-jessie.nl/uploads/files/97042275616.pdfIn PDF document text
    • https://nakatarikaszel.pl/app/webroot/userfiles/file/32130792005.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=redmi+9+vs+not+9PDF 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_off0000d01d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD01D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e82f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE82F 19080 bytes
SHA-256: a782d452413121e5bcb632a7cb4355fe2e76c3c75c2a580cc5453b45cf74a853
font_02_sfnt_off00011a14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A14 10380 bytes
SHA-256: 7e1f7cf418a75a5c399291e0fe2be842c912c52cd97473bd1d0f1a73848d66c2