Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5e59f0f2931da90…

MALICIOUS

PDF

87.6 KB Created: 2021-09-19 00:29:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ca1637dc5b4b5701729e15340d51e2d7 SHA-1: 65f77d870286274d51bae16a04a7084ba5a00266 SHA-256: c5e59f0f2931da90e5e49e869fb3ed88137e3d90ab602d16c978f39ad469fa3f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm directing users to various external URLs, some hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL analysis point to a malicious document designed to lure users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://stealthwindow.tw/uploads/files/202109112322535979.pdf In PDF document text
    • http://resortcrimea.com/ckfinder/userfiles/files/wewuzavorenoxan.pdfIn PDF document text
    • http://lagrupacio.cat/file/muvaxakapurerij.pdfIn PDF document text
    • http://julianina.dk/upload/file/8658533622.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/d227db824ed1371b1497868fe1b8e6ed/3254307019.pdfIn PDF document text
    • http://dkkarsin.pl/img/upload/files/tazik.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1614226443e3ea---ririvipage.pdfIn PDF document text
    • http://kezmosas.hu/files/file/tenufapanaruxipono.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/b8c318dd50e0b107d05c48f9b156f5f8/31276626453.pdfIn PDF document text
    • https://biholka.cz/uploades/userfiles/file/91223895381.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/8kvrdvk9m9kvkooahprtbsqth3/79581996188.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/getaz.pdfIn PDF document text
    • https://emmaushuis.org/pages/liwumivogefopabovojeregap.pdfIn PDF document text
    • https://newsale.linyn.mobi/upload/ckeditor/pages/files/mobomuvobinikuv.pdfIn PDF document text
    • https://brawlcall.com/ckfinder/userfiles/files/watudopuwan.pdfIn PDF document text
    • http://www.morrisjones.co.uk/EditorImages/file/dogetideponunetes.pdfIn PDF document text
    • https://almuhja.ps/ckfinder/userfiles/files/jipexajoregarofututudul.pdfIn PDF document text
    • http://museodegliarazzimarsala.com/userfiles/files/65705149909.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130700569ddf---31882912405.pdfIn PDF document text
    • http://gitishahjahanpur.org/ckfinder/userfiles/files/dugavigugebegafogudujof.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=ppsspp+games+2020+download+for+androidPDF 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_off0000ee42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE42 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010654.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10654 18676 bytes
SHA-256: 383e5cbf231b71c59591c25e04871b8da0ed256b5cac944c1286b53376b4ff6d
font_02_sfnt_off0001372f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1372F 11072 bytes
SHA-256: 2c4e488a3c212b1a6d51298ace1263fbe00932a968a40be81742aa59c94e729e