Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdb60a142ebb14f0…

MALICIOUS

PDF

75.2 KB Created: 2021-09-22 14:08:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e8353e3a5e91550d3bf4278c5e323774 SHA-1: 52503ca5c4d2a7d04c94af3a4df105897c42f39c SHA-256: cdb60a142ebb14f04e631d4ece42c98d016a1846b73d87722289e339c194c5da
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, directing users to multiple external websites, some hosted on compromised WordPress installations. The embedded URLs, such as 'https://chcial.ru/uplcv?utm_term=pay+per+download+android+apps', suggest a lure related to app downloads, likely a pretext for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://chcial.ru/uplcv?utm_term=pay+per+download+android+apps PDF link annotation
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e302dca33e---muzekozexutigamikefimix.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613329e69f593---ronesizotolurovisa.pdfIn PDF document text
    • https://vico-domrep.com/ckfinder/userfiles/files/25676154372.pdfIn PDF document text
    • http://delve-cr.com/uploads/xunumapalev.pdfIn PDF document text
    • https://gencshoworganizasyon.com/upload/ckfinder/files/88135500856.pdfIn PDF document text
    • http://forspeed.cz/ckfinder/userfiles/files/vagepi.pdfIn PDF document text
    • https://manuscripthandler.com/userfiles/file/rugowumerowogiv.pdfIn PDF document text
    • https://www.assofmt.org/ckfinder/userfiles/files/35335373453.pdfIn PDF document text
    • https://agatanorek.com/files/file/xolopitadixikikeditav.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/gojjibgvfu3mc9cb8rdsfn5ke5/wevonumezitawotibag.pdfIn PDF document text
    • https://tch.lu/files/files/kowome.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/90658311249.pdfIn PDF document text
    • http://forma8.kz/ckfinder/userfiles/files/40890164780.pdfIn PDF document text
    • http://miet-boot.ch/images/uploadedimages/file/poluwipodov.pdfIn PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/debizoloroxowosefajo.pdfIn PDF document text
    • http://nessie-vinylcare.com/file/70599622715.pdfIn PDF document text
    • https://behagi.eus/files/galeria/files/dudusirurizufuwipeguxe.pdfIn PDF document text
    • http://checopharma.com/upload/files/48395862253.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/xuwutuzaga.pdfIn PDF document text
    • https://futurefacesmiami.com/uploads/file/lelofuwopemibatedesetepi.pdfIn PDF document text
    • http://tamlaproject.com/userData/board/file/29211286434.pdfIn PDF document text
    • http://scea.edu.mn/ckfinder/userfiles/files/63906891908.pdfIn PDF document text
    • https://legyenegyjonapod.hu/userfiles/files/23890618932.pdfIn 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://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_off0000c234.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC234 10488 bytes
SHA-256: 63aee9c3409f773840088550f8e028018c1da088eb11f4dc53aa7ff90ee871e5
font_01_sfnt_off0000da26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA26 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f238.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF238 17532 bytes
SHA-256: d6d5429670a20cfe4ceb947eb9d7e15abd6f19e667a549211fddb9078a56f436