Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9a4e0ff52921e31…

MALICIOUS

PDF

75.7 KB Created: 2021-09-26 19:58:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 25b9b0bf3592a43badcd5070d82b1fe2 SHA-1: 9a829d8f527a053ddc160a94cf85c15972d3b473 SHA-256: c9a4e0ff52921e31183778b5f7b916cbdefae2dd370d7509729c1d87b44e07b1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

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://ketchas.ru/uplcv?utm_term=the+day+after+roswell+pdf PDF link annotation
    • http://nmways.com/uploads/fckupload/file/36919418376.pdfIn PDF document text
    • http://philipp-haberland.de/images/upload/file/5508768739.pdfIn PDF document text
    • https://taperagi.com/contents/files/16941505965.pdfIn PDF document text
    • https://mamap.in/ci/userfiles/files/3648289714.pdfIn PDF document text
    • http://saringkarnwood.com/UserFiles/file/63801695924.pdfIn PDF document text
    • https://nevisnews.com/userfiles/82943053494.pdfIn PDF document text
    • https://pelicanfinancialnetwork.net/ckfinder/userfiles/files/nifix.pdfIn PDF document text
    • http://www.kotolantopeni.cz/files/bululoraribixide.pdfIn PDF document text
    • https://learningsolution.ca/userfiles/files/jogesowupes.pdfIn PDF document text
    • http://eminenceinc.com/userfiles/file/koroxaditobawamedozojug.pdfIn PDF document text
    • https://0924055971.com/uploads/files/202109051829378430.pdfIn PDF document text
    • https://livre-d-art.com/ckfinder/userfiles/files/rojazezewufujoxekobokuko.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141736d01e66---93983119666.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/suubek8lfhmdumei61mipkes7o/26110630737.pdfIn PDF document text
    • https://eurochen.com/UpFiles/WebEditorFiles/file/mixakexifawu.pdfIn PDF document text
    • https://albizy.com/ckfinder/userfiles/files/84690802057.pdfIn PDF document text
    • http://oilmachineydy.com/d/files/94664719310.pdfIn PDF document text
    • https://okul.gencreklamajansi.com/uploads/files/5070107421.pdfIn PDF document text
    • http://mxag.com/upload/browse/file/tafinifosajoworoweru.pdfIn PDF document text
    • http://karpatskiles.ru/store/file/8830266774.pdfIn PDF document text
    • http://orosweb.hu/ckfinder/userfiles/files/39866442436.pdfIn PDF document text
    • https://best-of-geldanlagen.de/userfiles/file/muribogumel.pdfIn PDF document text
    • http://meteoratourismactivities.com/files/files/nevuxuxegixoguvo.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f55c0b48e2---55383006549.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b05f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB05F 16232 bytes
SHA-256: 01cd0e4798e93fb086042d610f43ddeed7bf091af48aa863f5c4a4f61b651684
font_01_sfnt_off0000c639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC639 10564 bytes
SHA-256: 24cab1b972c23fac405fe54eb068dc098166aaef6a984c2263ff25b2df464b71
font_02_sfnt_off0000de90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE90 16568 bytes
SHA-256: 826310c99239eedcf0411f0de5d31fc78830300ed4f4981f9fbc33c3e4e44d47
font_03_sfnt_off00010917.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10917 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1