Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b4331f76ff612c6…

MALICIOUS

PDF

82.9 KB Created: 2021-09-16 17:37:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f4f9ecf0e9a5e2f8bafb901cf120f3f0 SHA-1: 60272560ba1bb105c3b6987ea01ae4ffe6f9754b SHA-256: 3b4331f76ff612c6ab5706462088be7ae737de3d43b52202930b235b5d936f49
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external URIs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The embedded JavaScript likely facilitates the redirection or further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131be9893079---zurazupejowoxurudegufub.pdf In PDF document text
    • https://hainutedecopii.eu/ckfinder/userfiles/files/jubizapojovivo.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161300a12ce735---22724831569.pdfIn PDF document text
    • http://tsutae-f.com/js/upload/files/femumi.pdfIn PDF document text
    • https://aecvfcom.nrgence.com/upload/userfiles/files/5525707273.pdfIn PDF document text
    • http://kronospan-mofa.hu/editor_up/vofurikezakurejebamut.pdfIn PDF document text
    • http://kramnyca.info/img/upload/editor/file/94047315757.pdfIn PDF document text
    • https://tessuno.com/upload/files/613a3e1204461.pdfIn PDF document text
    • http://hanart21.com/files/userfiles/file/92548858713.pdfIn PDF document text
    • https://serka.com/serka/upload/files/nafifudixopunavenena.pdfIn PDF document text
    • http://kapsalonvogue.nl/files/file/misufakibotibekopoginim.pdfIn PDF document text
    • http://emotionpicturesfestival.gr/userfiles/file/46119624928.pdfIn PDF document text
    • https://gullyracing.it/admin/ckfinder/userfiles/files/52863026012.pdfIn PDF document text
    • http://njxinbell.com/upload/files/35125910668.pdfIn PDF document text
    • https://lemonsport.sk/upload/file/sonitarumapenusa.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/61fe69a53b6df250da68f5e1826ba017/79607615881.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16140354958809---73611804525.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/69068429139.pdfIn PDF document text
    • http://surausa.com/uploads/files/rulewer.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=development+through+the+lifespan+free+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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d47f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD47F 2468 bytes
SHA-256: 748f4161274a442c8e352ace714e45f35191e325b4e5a3073c83a186f91f51f2
font_01_sfnt_off0000df2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF2A 11112 bytes
SHA-256: 618608287cd17915d3a6f788d0f2160fb105cfc2a7b7d3e3e1eef6ff19abfeb5
font_02_sfnt_off0000f8a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A5 17004 bytes
SHA-256: b309bb26192244796975e5a66c6a7e732d6bd8568a484ff032f0c8612580f630
font_03_sfnt_off000124f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1