Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3d2e13eedb1a520…

MALICIOUS

PDF

73.2 KB Created: 2021-09-20 07:26:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: da0a1519886d4f7fb25b1ced90022ffe SHA-1: 6fb66ef10e422fb687f491b0eeafab4ecdafc37a SHA-256: e3d2e13eedb1a5201e5eaaaef49a7fb4cb0cde7ee7d2b5c05b001ba7d0b36c3e
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that form a link farm, pointing to various PDF files hosted on different domains. Several heuristics indicate this is a link farm on disposable or compromised hosting, suggesting a malicious intent to distribute content or manipulate search engine results. The ML classifier strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • 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 http://newabel.com/ckfinder/userfiles/files/55678451568.pdf In PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/fibukurijokotopuko.pdfIn PDF document text
    • http://chongthamphucthang.com/images/news/files/lirafapu.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161480be47b2d3---finukifijijetujezolekejiw.pdfIn PDF document text
    • http://candemdientu.com/Images_upload/files/fepakekazizudiwobife.pdfIn PDF document text
    • http://vinhomeshaiphong.net/app/webroot/img/files/jaxowuraji.pdfIn PDF document text
    • http://townofwinslowin.com/flash/townofwinslowin.com/file/6348781243.pdfIn PDF document text
    • http://vrajacreation.com/uploaded_files/userfiles/files/47990306011.pdfIn PDF document text
    • http://mikllc.mn/uploads/files/26146074399.pdfIn PDF document text
    • http://hondaototanan.com/upload/files/poxubig.pdfIn PDF document text
    • http://dongbanja.com/userData/ebizro_board/file/37761874436.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/rogenokimitapumog.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e5d0911ac---16159358059.pdfIn PDF document text
    • http://stroisvias.ru/userfiles/file/xebewevagemer.pdfIn PDF document text
    • http://kindergartenhelden.at/upload/file/fukewurorunojo.pdfIn PDF document text
    • https://nayyaralidada.net/alpha/ckfinder/userfiles/files/valuvejasijepesetijas.pdfIn PDF document text
    • https://bawauang.com/contents/files/40202347123.pdfIn PDF document text
    • http://cukiernia.eu/upload/files/wibusapetusinoka.pdfIn PDF document text
    • http://flemingdecal.com/uploads/assets/file/18720310111.pdfIn PDF document text
    • https://simbhaolipower.com/images/file/55805850145.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/161397d8b490e2---tamizijapoxaximoterosi.pdfIn PDF document text
    • https://alihuata.com/userfiles/file/pedube.pdfIn PDF document text
    • http://slsnn.ru/content/files/winute.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/161309097d8362---65947814971.pdfIn PDF document text
    • http://baldonimarcostudio.eu/userfiles/files/kataw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=or+in+android+studioPDF 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_off0000bd10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD10 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d522.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD522 16616 bytes
SHA-256: 4c54d98292bd0bd1429f8f2fc6ae974f9b35474cd93d2f26187fe2a8ae222333
font_02_sfnt_off00010079.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10079 10188 bytes
SHA-256: bb1515c3041eddc5ba1a75394608148ba9212f0de8147ff797b9e494d14477a0