Malicious PDF — malware analysis report

Static analysis result for SHA-256 f631b389ac330a0c…

MALICIOUS

PDF

85.8 KB Created: 2021-06-26 18:25:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c4539bbfff7e2e79dd8db20f82301f4a SHA-1: 56dc0f9e164593a83fec2ffd071b2a73c2c047d6 SHA-256: f631b389ac330a0c1b76095a48b119d795c6ef1ad596638b2af3804bb8a02598
164 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, many hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://huntic.ru/uplcv?utm_term=the+upsc+odyssey+pdf+download
    • http://waelfawzy.com/userfiles/file/75417204062.pdf
    • http://worthingtonpark101.com/userimages/kevoredopotixulimexew.pdf
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/bowas.pdf
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c8e990231f8---tadupexomosoti.pdf
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/opd0dtapc2vh0o02f1nsga4gj8/89805140602.pdf
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/09740b0095fa4d5de567c324fc49b032/66680333992.pdf
    • http://lezeckastenakosice.sk/upload/files/87029695382.pdf
    • https://dijitalsanat.link/upload/files/doxuguwosozebokujapu.pdf
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e9af8945fe---85881826164.pdf
    • https://allcreaturesinc.com/files/files/kananukelup.pdf
    • https://steklo-shik.ru/userfiles/file/34676612382.pdf
    • http://tz5168.com/uploadfile/image/2021/05/16/file/20210516_172131_145.pdf
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf36f3e3bab---gagakeketav.pdf
    • https://www.kcequipment.com.au/wp-content/plugins/super-forms/uploads/php/files/ab80afc6366064e87260feaf7310f4b0/telazamepixa.pdf
    • http://kotolantopeni.cz/file/26674480435.pdf
    • https://equantumconsulting.com/files/files/xedasebafufevuras.pdf
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/49cqhnimdqi09na81m5o0d0q3d/40313629585.pdf
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b600df393d4---39559937410.pdf
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c91b20dcdf7---nosizedaxoxunasile.pdf
    • https://bluetact.com/ckfinder/userfiles/files/roxamijekofofolazok.pdf
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/1athfov46319ulg562ci4c9um2/jumogopun.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eb3c.bin
cf918979e14c730f11afd654806cb23ea43c336407ea35d3d1e347c10b9ffd15
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB3C 17624 bytes
font_01_sfnt_off000119c5.bin
1fa72eedaef32df705e129c40707654c5a9881ba5b4984d055453258bb32ea38
pdf-font-stream PDF embedded font (sfnt) at offset 0x119C5 10688 bytes
font_02_sfnt_off00013253.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13253 16792 bytes