Malicious PDF — malware analysis report

Static analysis result for SHA-256 54a1037f4171af76…

MALICIOUS

PDF

78.4 KB Created: 2021-06-25 15:10:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: fc18e4f00ae12943349422f352e7b533 SHA-1: 4614163cdcd29cba3b943b066767c7721e420ee3 SHA-256: 54a1037f4171af76d6ad0d8afae1483f2a15ae4426c1b8a703e45c2670216340
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The structure suggests the document acts as a link farm to distribute traffic to various malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://tonitomov.com/picture/file/50248475678.pdf In PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b48bfac9378---62687800052.pdfIn PDF document text
    • https://alperbehang.nl/userfiles/file/2779486007.pdfIn PDF document text
    • https://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/8655a0b776c17af55a93b60bba4cdcda/migef.pdfIn PDF document text
    • http://kleinschaden.expert/userfiles/file/lewekurogitabaweler.pdfIn PDF document text
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/15001243ce0089c1f3a6460677a61153/bipimagapinurerewukemuli.pdfIn PDF document text
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1607197743f145---dijep.pdfIn PDF document text
    • http://xboxheerlen.nl/userfiles/file/54984716759.pdfIn PDF document text
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160978ae1a36d0---neboxifutebemisibid.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/160ac4a385d357---puzusonoku.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/16092fa35896b2---29432102412.pdfIn PDF document text
    • http://homenet-spb.ru/userfiles/file/47932922405.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608f49dd63f91---nupinopubeze.pdfIn PDF document text
    • https://syteq-pro.com/userfiles/file/tatelixi.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/6c22973ac6440fc4366c9c5db2eaa86c/nifezikosol.pdfIn PDF document text
    • http://fzsvybbs.at/userfiles/file/40266223260.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=hsv+for+salePDF 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_off0000cd80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD80 18104 bytes
SHA-256: 93468b29a99dae966e32f8e881cabec28e5fa4f5b49341fa75a1ea2d3169299a
font_01_sfnt_off0000fd8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD8B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000115a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115A1 9968 bytes
SHA-256: e42fb259b4c824340bae8b5a4c9fdef374c27a19a83b38e5153fe7be408dc122