Malicious PDF — malware analysis report

Static analysis result for SHA-256 c537256591474bd3…

MALICIOUS

PDF

76.9 KB Created: 2021-06-19 04:11:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 8827e639f2d54bf0093f66852e2241c7 SHA-1: eaeeaf55474c0fd1cebc2eddee4f98b602187c19 SHA-256: c537256591474bd32005e8295dcfffec2621b99f73f9056d22a01607d4bb6607
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. The file contains numerous links to compromised WordPress sites and disposable hosting, suggesting it functions as a link farm to distribute malicious content or phish users. The presence of embedded URLs and the nature of the heuristics point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1607cc575a1bc9---98371095210.pdf In PDF document text
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/58375ee30904c985b5555b071240b759/mitomop.pdfIn PDF document text
    • https://flyags.com/editorResources/file/%5C/27213204995.pdfIn PDF document text
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa365adae9d---17603753604.pdfIn PDF document text
    • http://promador.pl/userfiles/file/jakuras.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/556660aa936ead5ace28bfaabfb91d0b/21758977207.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/69vq3covvm86f0s0lp41r7f4hi/givadupop.pdfIn PDF document text
    • http://zartmobilia.com/userfiles/file/20210527020616.pdfIn PDF document text
    • http://arci-mp.fr/admin/File/guxagowezafugofixela.pdfIn PDF document text
    • https://nhathuydesign.com/wp-content/plugins/super-forms/uploads/php/files/1dcnb3ilh8n2b8uaf0ppqmphg2/zusexibisu.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3da48b7f8---zenudomozomukupikudivok.pdfIn PDF document text
    • https://vieclamday.com/userfiles/file/69220893366.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a92951519ec---3230288748.pdfIn PDF document text
    • https://agentcctv.com/userfiles/file/60047728298.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160abe958adb92---69066850741.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16082a341ae5ff---13491401534.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/33bb7acb81c58e4db82253d3464ed125/juzolokab.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/bbd9cbd429f621fe7001ef15dab0cc3c/bazusaxugaxibowebip.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=date+a+live+gentaiPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f300.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF300 4640 bytes
SHA-256: 6b6624ab94d2b5853a58eaddf6b90b611c6a3d9c70375af283cc6400a9ca389a
font_01_sfnt_off000102ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102ED 10564 bytes
SHA-256: cc6cac4627332de9b148aca663c41c3ca2638ac6e50b16974d61afe2db992fdd