Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c1543c6f9a1556a…

MALICIOUS

PDF

72.8 KB Created: 2021-07-13 07:13:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 40bc91447db5df7aee61f2edaa38442f SHA-1: 3c610d14f7790f67006c99a8ba8405418f77ce5a SHA-256: 8c1543c6f9a1556ab0d71b258cd85dbe16467cd2d1702c68208226f2380f4171
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to compromised CMS upload directories, likely intended to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics strongly suggest an attempt to lure users to external sites, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160b9897cc6d8c---91324644758.pdf In PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c6ba3892f7---logovafe.pdfIn PDF document text
    • http://trickorsuite.com/clients/5/5d/5d84d12f6f4dfd10bbe5497c884a5f3e/File/71874019192.pdfIn PDF document text
    • http://axwelindia.com/uploads/25808481345.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/21150f774e7b4ef711583c80522f9882/1663211984.pdfIn PDF document text
    • http://statewideroofservices.com/clients/b/b8/b825a24af54c157c196cf52173d75bf0/File/8450910061.pdfIn PDF document text
    • https://mobiligennari.com/userfiles/file/maselajuso.pdfIn PDF document text
    • http://yjccnc.com/upload/files/xukugogokovirunogozewug.pdfIn PDF document text
    • http://webbuilders.com/files/file/14669663302.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160ab28f42dcf4---daxuniba.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c707e985b0---vozolibidibimaxe.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e08d5ee1db5---9685105811.pdfIn PDF document text
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/i4611qughkev24c3enkqv63gu6/manupuba.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/g8qjh5ic7nbbbds99v6kiv9juj/60627188394.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609443d6d9856---zoronalamo.pdfIn PDF document text
    • https://khabul.mn/mmpa/userfiles/files/xalunenumil.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab50e08fbeb---94226777580.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/55665773001.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/609f39974acaa5094acfc0781d4085c8/pazepijarogosumixewi.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c50706647a3---53032134417.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0e98e279383ffd0119720905148d7749/vulovesosiwaxe.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/094766f006481f999d3c267022b55015/pifumexisolovu.pdfIn PDF document text
    • http://efuegypt.org/userfiles/file/tavijipijuboterefigeludo.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/a9a73b3e09daba24128460531cf65bea/36862831036.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=norbeck+social+support+questionnaire+pdfPDF 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_off0000bd32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD32 15252 bytes
SHA-256: 64b2b4d6be102daa26be1aa85d61c634966911d2ba5a36056a09fd43a9961bf4
font_01_sfnt_off0000e3f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fc0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC0E 11068 bytes
SHA-256: 2e2c02c2aef6faa9160bcc68d43e3d8cd45ae1da118f170eea05deb3d73eb784