Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad25339e4e3d562a…

MALICIOUS

PDF

73.3 KB Created: 2021-09-07 20:46:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 307b666562fc3ac89c5f216c3b08a6fe SHA-1: 07503762e2f88210f08358009bddfee7696dbbb6 SHA-256: ad25339e4e3d562a39f8b3153c2209f250819225c8071c2b4a50538a7df64d30
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, which in turn host other PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as phishing. The presence of a link farm on disposable hosting further supports a malicious purpose, likely to obscure the ultimate destination or to distribute malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ab6344e210439209a5717a586e4570a8/91303164185.pdf In PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e2f6353664c---21055650900.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/ccc4fbcd5aca7aaf106ee99f5e5c4b62/28144040396.pdfIn PDF document text
    • https://xn--mgbaf4adbs1bd2i.net/upload/ckfinder/files/16472169273.pdfIn PDF document text
    • https://argumentua.com/i/file/sotanimus.pdfIn PDF document text
    • http://arebiatours.com/uploads/files/guwabivezelepivasez.pdfIn PDF document text
    • https://landatur.com/files/galeria/files/79138213214.pdfIn PDF document text
    • http://tiendanatacion.com/noticias/files/popal.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/jgksnbnj8t1rec2uie4uecoua1/99842566830.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160bd016dd15ba---ritivalusedugusupowetivo.pdfIn PDF document text
    • http://wjcopy.com/upload/files/31050453712.pdfIn PDF document text
    • https://candica.pl/ckfinder/userfiles/files/jogiridupepa.pdfIn PDF document text
    • https://t2sc.me/userfiles/xavowofizemifuwigokawo.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16080a29f8eaa2---52904168488.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/27407405137.pdfIn PDF document text
    • http://tubemakingmachine.com/uploadfile/files/87865019477.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acd1689e8d3---sedamitutimofimebexaduk.pdfIn PDF document text
    • http://debsecond.net/UserFiles/File/nuditizuzujekisizoti.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/f3d99802505973548de1f73351987490/gogojudisajibupaxeb.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/jutox.pdfIn PDF document text
    • http://thaoduocquyhiem.com/userfiles/image/file/wafim.pdfIn PDF document text
    • http://bostonmentors.com/userfiles/file/1138361458.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/846ad2ded464c87e84fb688d250554d2/lemapusejuseniradewatuve.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=multidimensional+database+pdfPDF 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_off0000bbce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBCE 16732 bytes
SHA-256: 37da309515db6450b53de680cce1510a4c4dce84751d9dbca5e57c561b8938f4
font_01_sfnt_off0000e6e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fefb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEFB 10792 bytes
SHA-256: 93d5b27192af11bc564608d16212c1a81597ea27a894151aaf169b21a759047d