Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c61a0c291e016f3…

MALICIOUS

PDF

86.2 KB Created: 2021-09-12 02:35:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: aa587fc7cea073573e84f2fdab541a35 SHA-1: 1cbbae02a9ebf52bfe5201d52667417f10db9381 SHA-256: 8c61a0c291e016f3ac8d7d9b9f6ae9d7b5216a36a6af70def21f936a61d39e18
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. It contains a link farm pointing to compromised WordPress uploads and other disposable hosting, suggesting an attempt to redirect users to malicious content. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d807aec650b304589b57f4f602303828/zepunulifuwidibuno.pdf In PDF document text
    • https://texasbordervolunteers.org/userfiles/file/morazuxug.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/8d22aee9c1f844b53b0e819b28644704/46752398549.pdfIn PDF document text
    • http://fornacedelia.it/userfiles/files/lipujumoxobifibup.pdfIn PDF document text
    • http://klenderbio.com/upload/files/nukevo.pdfIn PDF document text
    • http://lnhaihui.com/userfiles/file/20210902010838_371350852.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/2688b96c70e6a3485ea45a28af87564e/belaletuwisimafeba.pdfIn PDF document text
    • https://aihr-iadh.org/uploads/FCK_files/file/86816436677.pdfIn PDF document text
    • http://webinaris.blog/ckfinder/userfiles/publics/files/fikibuzuwatogosala.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/22692501035.pdfIn PDF document text
    • http://chieusangducphat.com/uploads/userfiles/file/56901872359.pdfIn PDF document text
    • http://njchemland.com/upload/files/51911043400.pdfIn PDF document text
    • http://philipwillettelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nekifumibewakobapozoropup.pdfIn PDF document text
    • http://www.groupementpecheduloir.com/ckfinder/userfiles/files/38124116612.pdfIn PDF document text
    • http://marketypik.pl/zdjecia/fck/file/11692712534.pdfIn PDF document text
    • http://paneldeconsos.com/userfiles/file/88227437707.pdfIn PDF document text
    • https://dolaodong.com/userfiles/file/94573559436.pdfIn PDF document text
    • https://glaze-metalart.com/upload/files/76297106057.pdfIn PDF document text
    • http://0-50.ru/userfiles/file/34041398018.pdfIn PDF document text
    • http://veterinariacasettamattei.it/userfiles/files/pelul.pdfIn PDF document text
    • http://custom-mugs-factory.com/uploadfile/files/nupamejeb.pdfIn PDF document text
    • https://kop-trans.pl/uploads/userfiles/files/63203124753.pdfIn PDF document text
    • http://location-appartement-venise.com/italie_documents/files/86779464548.pdfIn PDF document text
    • http://northmarking.com/userfiles/files/wugimimaxafololagu.pdfIn PDF document text
    • http://chiangmaicharmingtravel.com/ckfinder/userfiles/files/zojevatapikerotefel.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+install+apps+in+android+autoPDF 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_off0000ee4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE4A 17436 bytes
SHA-256: 45485014356221f28235b99238932074c2d12b96f19a32847610252b798a51e0
font_01_sfnt_off00011b39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B39 10428 bytes
SHA-256: 70f3b808e9b4206027645bcf2fcb7a75818b6c89d146634b6bc6c720bec20b0f
font_02_sfnt_off000132f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1