Malicious PDF — malware analysis report

Static analysis result for SHA-256 18a142c7ad3f98c9…

MALICIOUS

PDF

77.6 KB Created: 2021-06-11 23:45:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 5040a1702225054cfb4fd9e48e5a5a56 SHA-1: e4caa2e7743525eefd627a4ecccf58c8ff5b2eb2 SHA-256: 18a142c7ad3f98c953268e7483c7e176e871a11737cbc80cb4c77efbbda59bdd
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to various PDF files hosted on compromised WordPress sites, likely as part of a phishing or malware distribution campaign. The embedded URLs and the nature of the link farm suggest an attempt to obscure the true destination and evade detection.

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 https://huntic.ru/uplcv?utm_term=attestation+de+vente+chiot+pdf PDF link annotation
    • https://bestcoloringpages.com/userfiles/file/93260708760.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098f64f8e8c4---53683763668.pdfIn PDF document text
    • https://porterbrothersltd.com/app/webroot/uploads/zigaxo.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1606e140ebc4cb---nexurixov.pdfIn PDF document text
    • http://ash-graphy.com/userfiles/file/13512732312.pdfIn PDF document text
    • http://bsbcarpet.com/userfiles/file/nogavez.pdfIn PDF document text
    • http://aeronautike.com/userfiles/file/devitukenetoxexugogusejox.pdfIn PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/16083ce3e7af73---30238764698.pdfIn PDF document text
    • http://karmand24.ir/basefile/ehotel724ir/files/27088289124.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16074d1e661a48---48229843211.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/c6095ea075e2d69d65623e7191c684df/92665357977.pdfIn PDF document text
    • https://medsplus.us/admin/images/file/38444044509.pdfIn PDF document text
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/c190ebacf5720c132e3659fcfe5810a6/lixivaxilozusilajiri.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/d740edbab486262db9ad10a4bc6e4bb5/45077744175.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/be46d82504b8cd12ab2bb057bb802bd6/74981380758.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1608757ca0ad8c---32622447143.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/bbe37c1bd1f70fd6af4c4847b717dfdc/44219493247.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eede.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEDE 5164 bytes
SHA-256: 0261a4e97a4473d2dadc428d142e16e81bdd1c4816ea23cb406b516ece42cc0d
font_01_sfnt_off0001007d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1007D 12040 bytes
SHA-256: c741445e3c4a3ac04e38c8710191948bce5363479289a2a15b39db6bfe0dc6c1