Malicious PDF — malware analysis report

Static analysis result for SHA-256 53e766cdea6af2f2…

MALICIOUS

PDF

68.7 KB Created: 2021-09-24 14:09:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bdec7eba766c4ba5316794d1f37dd7c9 SHA-1: 75ea506b7330a894b864e603fc6674ed13a2e789 SHA-256: 53e766cdea6af2f286e8996604b3d35a74d78e3e1971894b201b55cc6c69c42a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple domains, many of which are hosted on disposable or compromised infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://kominove-centrum.cz/media/files/file/gisilezimetalutir.pdf In PDF document text
    • http://leaguengn.com/userfiles/file///65107164203.pdfIn PDF document text
    • http://altronic.pl/!mag2011/userfiles/file/rosopuxepudutobojixu.pdfIn PDF document text
    • http://westhollywood.ilovepokebar.com/uploads/files/jigupelibiveloxuruzuler.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/161418a150a88c---4541204427.pdfIn PDF document text
    • http://efrex.cz/files/file/gogukefuxabisev.pdfIn PDF document text
    • https://www.gico.ge/ckfinder/userfiles/files/kemoketobifik.pdfIn PDF document text
    • http://tortsurprise.ru/upload/redactor/files/56452382488.pdfIn PDF document text
    • https://fratellifurloni.it/file/7302743720.pdfIn PDF document text
    • http://hyswimpool.com/userfiles/tuwozomojapowawutan.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16147a5fdca815---67622023106.pdfIn PDF document text
    • http://scsychem.com/upload/files/92343249307.pdfIn PDF document text
    • http://inwama4.vn/webroot/img/files/dadutuwurelap.pdfIn PDF document text
    • https://promoxcenter.ro/ckfinder/userfiles/files/virisixek.pdfIn PDF document text
    • http://fcvperu.org/data/fcvperu/userfiles/file/8651284200.pdfIn PDF document text
    • http://www.bandungmesin.com/file/wozawazelenufa.pdfIn PDF document text
    • http://taiwan-casters.com/userfiles/file/nufuterofoki.pdfIn PDF document text
    • http://www.wm-meyer.de/meyer/admin/editor/ckfinder/userfiles/files/29175541621.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148e79e986f0---likivekuwe.pdfIn PDF document text
    • http://millenium.moscowfashion.net/content/xuploadimages/file/84432552070.pdfIn PDF document text
    • http://pokewaveanaheim.com/uploads/files/nuvaretimukuviniloji.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/161319628dad88---82362746285.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=sat+1+answer+keyPDF 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_off0000b08f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB08F 14804 bytes
SHA-256: 90002ae63de480867ddaeda57e04417f0fc59c487484a5bfee96e6e664a9dc16
font_01_sfnt_off0000d5f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5F8 10260 bytes
SHA-256: bbc1877e31f52c51dc75d3ae575cee92f05d1f061e81fbdf72c6e10208226a1b
font_02_sfnt_off0000ed5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED5A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1