Malicious PDF — malware analysis report

Static analysis result for SHA-256 a761c85a389c776f…

MALICIOUS

PDF

73.1 KB Created: 2021-05-02 03:35:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 15418090483d9fe13290d9e088a8a4c6 SHA-1: 6ea16ebea02c974ff5d08796549bba8fc777296f SHA-256: a761c85a389c776f6c198edf553b9bd4089b494f55fabf2b5aabc5243eda80c4
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, pointing to multiple compromised WordPress sites and disposable hosting. The embedded URLs, despite some being marked benign, are part of a pattern designed to redirect users to potentially malicious content.

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://abril.pe/wp-content/plugins/super-forms/uploads/php/files/8gie1asoukli3a1jkb6ned3fvi/90756578303.pdf In PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/d8498abee10e02452b94dfd4ae2e531c/41208704442.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d248af0454---gakokegotujopunoruvavudo.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cc4f0af7c3---wadilirowejivero.pdfIn PDF document text
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/301146d14231b72ed08e7342bb60c02f/kopugab.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608649f84b113---fuleron.pdfIn PDF document text
    • https://cursosgratuitosonline.es/wp-content/plugins/super-forms/uploads/php/files/1i84sg1bm879b5jgfljv0jqjsh/neviligalizusulud.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/a2e71d30a354047e434f83be8b5490c5/zivuxuzapujelozupesigow.pdfIn PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/h0b78887d69clct50a50suvrhh/zuvemusimituf.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082ecb7a9071---90674768960.pdfIn PDF document text
    • http://middlegeorgiacoinclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd1e40c816---11659192985.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/02ccf1afb3d4a61dd93e30bc5f6de238/18633368366.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/d71619a7d6346bd982e3809008dfab0e/96319884454.pdfIn PDF document text
    • https://www.zaantraining.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608b2455206c4---mafatemafikoresolazo.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/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=android+authority+app+not+workingPDF 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_off0000e1a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1A9 5256 bytes
SHA-256: 1790262e62133ec9ebf5fb345c15d0c53eafdf1cc9aa193fd88bd8ea1af6cc8c
font_01_sfnt_off0000f3a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3A3 10432 bytes
SHA-256: dbb30f27817c908260fdddf88f40f3257d86940b385326d96fdfe36de16e243e