Malicious PDF — malware analysis report

Static analysis result for SHA-256 42f543f5cafef8f1…

MALICIOUS

PDF

70.6 KB Created: 2021-09-06 09:37:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6d940c8ea0544eee026557e80464cc0d SHA-1: 0a4bb2400c2ae77faff8223e48dc7a747601b875 SHA-256: 42f543f5cafef8f10cb90632e3753b6204d15e8196bcc39e75fa99fd56de9d2e
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to compromised WordPress sites, suggesting an attempt to lure users to malicious content. Heuristics indicate the PDF is designed as a link farm on disposable hosting, and ClamAV detected it as a phishing trojan. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607edc6a931dc---98635863089.pdf In PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/1b41c9133fe6a7ddaa674fb88d5f78a7/sixifaxewupu.pdfIn PDF document text
    • http://homelife-superstars.com/image/files/zanibuvi.pdfIn PDF document text
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/6a4ba1e93a3c153ba4d05ac4ca417abd/65763829420.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4b3c54b8ae---23050689589.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/623b25a8d8938566df7b5d7e0dc60e65/toxasugisolixod.pdfIn PDF document text
    • http://miyozenemeryville.com/uploads/files/simotede.pdfIn PDF document text
    • http://dhleisure.com/ckupload/files/31674842617.pdfIn PDF document text
    • https://sensiblemachines.com/ckfinder/core/connector/php/files/38722286435.pdfIn PDF document text
    • http://xn--xhq021fvrwdth.com/d/files/67931963061.pdfIn PDF document text
    • http://www.catedralirodahaz.hu/data/editorfile/33127624350.pdfIn PDF document text
    • http://donghozibistore.com/luutru/files/1435006722.pdfIn PDF document text
    • https://csn-alliance.com/data/files/sowubikexagexaguwu.pdfIn PDF document text
    • http://kiszelyugyvediiroda.hu/docs/file/77598062935.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160a3e40f54a75---busumozelixusuzitob.pdfIn PDF document text
    • http://leton.pl/userfiles/file/38788710280.pdfIn PDF document text
    • http://bestapp4u.com/admin/uploadedfiles/file/69260594318.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/cb5bd18a6ce0cffa8eadbe9c5cce10f5/bafajezojakegojujapozunul.pdfIn PDF document text
    • http://szentimresiklos.hu/upload/file/11526794216.pdfIn PDF document text
    • http://hodinovysoused.cz/upload/file/pefug.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/fdf5b45a6ebbf00b9dc6711f016bc7bc/17450341130.pdfIn PDF document text
    • http://www.parkwaytransplant.com/media_upload/upload/files/bumadaxotone.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e087596b70---37573770866.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac8d2158c91---76694620698.pdfIn PDF document text
    • http://ithalattagarantibelgesi.com/resimlerfiles/nudaduxujofupusiteta.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=present+perfect+past+simple+exercises+4+eso+pdfPDF 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_off0000b57f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB57F 15180 bytes
SHA-256: bb7fc4242cd1f4011559b8bcabb38ac6da1362531581a5c439c80dedf662a21d
font_01_sfnt_off0000db26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB26 10960 bytes
SHA-256: 19ba0f97bd259a1488a290d095988ed27accb8185520af81af9e11cfa735611f
font_02_sfnt_off0000f4a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1