Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fddb6d96f647688…

MALICIOUS

PDF

67.6 KB Created: 2021-09-20 00:03:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: f363984d7bd75bb46c941552428d1ce4 SHA-1: 0a167d045c67f4b89adca7871f0ea67cdd0e673e SHA-256: 3fddb6d96f647688f261a82fdb423c9a8858b472ccd55e77695478aeee031914
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised WordPress upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farm heuristics points towards a tactic of luring users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://synerhu.ru/uplcv?utm_term=adblock+browser+android+download PDF link annotation
    • http://gibkrakow.pl/uploads/files/16857479079.pdfIn PDF document text
    • http://positiveforce.in/uploads/files/89637582272.pdfIn PDF document text
    • https://waelfawzy.com/userfiles/file/In PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161317e26b19fd---xosubododu.pdfIn PDF document text
    • http://biaikatolikus.hu/files/file/nilodavidimovedefizu.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/16146dd9a81d6d---20162473526.pdfIn PDF document text
    • http://cloverdiamond.com/file/15350990801.pdfIn PDF document text
    • https://newtech-utm.pl/userfiles/file/73928407037.pdfIn PDF document text
    • http://mjacz.cz/soubory/files/jimejisutaduveza.pdfIn PDF document text
    • http://lblussana.it/images/file/81236627483.pdfIn PDF document text
    • http://abnicum.com/files/file/kowaxagovala.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/e39c2298516613bf2b811a37beecb90b/nivezirizimaxagajeli.pdfIn PDF document text
    • https://sim2007.com/files/20234962359.pdfIn PDF document text
    • https://strongpointmarketing.net/userfiles/file/90226253872.pdfIn PDF document text
    • https://aurorabersinar2.com/contents/files/41005799028.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/tikewutu.pdfIn PDF document text
    • http://yer-krasnodar.ru/ckfinder/userfiles/files/99022468338.pdfIn PDF document text
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/428882b5f952f24a9901d3ee347af7a0/bajexusadusomugemesige.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614431ac42878---zizux.pdfIn PDF document text
    • http://sevimticaret.net/userfiles/file/tusevexedase.pdfIn PDF document text
    • http://wami.cc/data/files/bizaguvuzugasisapil.pdfIn PDF document text
    • http://studiolorenzino.eu/userfiles/files/luvomer.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_off0000ad2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD2A 14380 bytes
SHA-256: ab4ef63f14e8fb8597669d74a4c07843f592d5370c93bd5336cda16e1d81f5e8
font_01_sfnt_off0000d0f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0F5 10564 bytes
SHA-256: b6420a0f0c39de315d6473df1446bf82ff9185f60383dbdd0b94feccf25c0b1e
font_02_sfnt_off0000e934.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE934 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1