Malicious PDF — malware analysis report

Static analysis result for SHA-256 f55620cfcb69e030…

MALICIOUS

PDF

79.5 KB Created: 2021-06-13 05:04:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 065461c5b598e7a82d1b13500ad10bb0 SHA-1: d12878edd6043198c9eab66a7d9e7cf9f6587cb3 SHA-256: f55620cfcb69e03016ee8c3d66eba58024783790030fd635420220e615bddb81
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous external links, many pointing to compromised WordPress sites, suggesting it functions as a link farm to distribute malicious content or phish for credentials. The document body is heavily obfuscated and contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://infrive.ru/uplcv?utm_term=tina+dabi+upsc+answer+sheet+mains PDF link annotation
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095dbec08db3---47927489011.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/8579363fab0923d22116554f48128da8/pimodinuditibufum.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/79aeca87b0f6b6e3b58a487e53f58d48/buzajotugivesopa.pdfIn PDF document text
    • http://soflocops.com/clients/67403/File/pezagulinujivon.pdfIn PDF document text
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/b5f72ee489508f24396fb1ded0c08b6f/66863864531.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0332637228---gitix.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607321fd46419---babumufarewelujebogap.pdfIn PDF document text
    • https://jagominum.com/contents//files/905463305.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b21d783a42---tuvikifuliten.pdfIn PDF document text
    • https://hashtag.school/userfiles/file/gamivirexa.pdfIn PDF document text
    • http://zap-interactive.com/uploads/files/lafozukokilejiwo.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac2130e1e9---rikamonibozufibeditaza.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/05181eb941c47648d10446ee066f756e/kukixubasonobiwet.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/b2270fbd02a4c8df5430cf5c946ecbd7/50211450396.pdfIn PDF document text
    • https://e-fasteners.eu/media/file/vojiriw.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC8E 5236 bytes
SHA-256: eb72619df5a5d389b3a560c6db8b856f4fa76fceaa0de02c890e0863e6e7ad23
font_01_sfnt_off0000fe2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE2D 10744 bytes
SHA-256: 71cd5edc7e3ddd3c710271746734626013e462d1dc81b0ba29b8c6bd74d287cf
font_02_sfnt_off000122fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122FE 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f