Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a3ae5835b409146…

MALICIOUS

PDF

84.7 KB Created: 2021-06-10 12:14:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 2e18b6fae4b2a3295236ad8674634586 SHA-1: 9602faa1d257e46321d53a05010aee6d04622bbe SHA-256: 0a3ae5835b4091460acbcef90a264f0d96df0daf4abb0e75e6bbfbae14959b05
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://pistant.ru/uplcv?utm_term=latest+yowhatsapp+apk PDF link annotation
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/3424ec4c062ab286e8da731b728f3572/tokolo.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/3aa06a6dd6406d417a9d6cef2e94cf8a/bijelevofevonebuzojije.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160834b4d8fc97---sonudanobalitopedetuze.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fc8cbcaa1b---53892813739.pdfIn PDF document text
    • https://www.justgym.co.za/wp-content/plugins/super-forms/uploads/php/files/u5fghpjafn821eo761qlmvjf4d/xadotelusodox.pdfIn PDF document text
    • http://i-daa-wl.de/userfiles/ropedaduvopemodepixi.pdfIn PDF document text
    • http://bmhs1963.com/clients/7/72/7286fd37811b7a5dece6e69924e4d5ab/File/39999947738.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607990d27a6b4---bukofubuvatilowezozuj.pdfIn PDF document text
    • http://cosmic-kino.ru/sadm_files/64106001561.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/db20c267cf001a879fcb6911a7416208/kosikaporuwesabefamise.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/44728183951.pdfIn PDF document text
    • https://birudongker.com/contents//files/34353352484.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000fa81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA81 4976 bytes
SHA-256: 0ebf5be058b3704673d48017af3d8c03d5583da8a960a8e93f19fbac13c80069
font_01_sfnt_off00010b88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B88 11096 bytes
SHA-256: 1a7c59f102913da451bf4680f45f32d3cbefc020138a5a3ba15c193d234b3072
font_02_sfnt_off0001315f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1315F 16092 bytes
SHA-256: e9fe716c2abc985b12a899a49d5539e4e8be1b56d50c083b30290d85a2a7c848