Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e3f9f88e75e43e0…

MALICIOUS

PDF

66.5 KB Created: 2021-09-22 18:06:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 395b5b96dbef61439f876dc341204d5c SHA-1: 13dffc33a981059e00669832834bdf3b9dc393c7 SHA-256: 8e3f9f88e75e43e0db5676b8f8b74316019fbbfc8294e5e018fc6204bb1098ae
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF exhibits characteristics of a phishing lure, including an image-only design and embedded links to external sites. Heuristics indicate it's a link farm on disposable hosting, with some links pointing to compromised CMS uploads. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to malicious content or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 66 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://inwebjor.ru/uplcv?utm_term=4ukey+download+android PDF link annotation
    • http://wxmx.cn/upload/ckimg/files/202109170658318103.pdfIn PDF document text
    • https://inchiriereelicopterromania.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613927cb0c393---karagodajinexodirov.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/16143668be177d---xugupowa.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/bemoriwonakazesi.pdfIn PDF document text
    • https://rajaketiga.com/contents/files/nejotobemopexol.pdfIn PDF document text
    • http://sial.pl/galeria/file/xuxilugugusozidifilalimul.pdfIn PDF document text
    • http://startent.ru/SITE/files/editor/file/ditolirevosasuriwavivopon.pdfIn PDF document text
    • https://valergences.fr/userfiles/file/nomadanuwapozomuvozewu.pdfIn PDF document text
    • https://essuances.com/ckfinder/userfiles/files/26540371832.pdfIn PDF document text
    • https://jazykovytabor.topenglish.sk/app/webroot/gallery/files/15113981847.pdfIn PDF document text
    • https://suruburi.net/mm/file/vekufewulagus.pdfIn PDF document text
    • http://llux.vn/uploads/files/dedeku.pdfIn PDF document text
    • http://shbaicun.com/userfiles/file/2021091109592273499.pdfIn PDF document text
    • https://chasehr.in/userfiles/file/29315295499.pdfIn PDF document text
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/68785fbe4d741f503054a875ea596d96/kiruwepowi.pdfIn PDF document text
    • http://signauction.net/userfiles/file/55966097126.pdfIn PDF document text
    • http://samtle.net/ckupload/files/77945397382.pdfIn PDF document text
    • http://cottoneauto.it/userfiles/files/bokojimugane.pdfIn PDF document text
    • https://albizy.com/ckfinder/userfiles/files/wododekojivikuromasuzuj.pdfIn PDF document text
    • http://thietbimaugiao.vn/Images_upload/files/8822762297.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_off0000aa95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAA95 14060 bytes
SHA-256: cebfe7953655f5100199ee78923312f8f532c711fbec301537fc12c6ce8e8656
font_01_sfnt_off0000cd78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD78 10348 bytes
SHA-256: abbf3ea8dff40fd571cce425b9ea606e42c7cab67ef7f22172772c3cb2da37cd
font_02_sfnt_off0000e502.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE502 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1