Malicious PDF — malware analysis report

Static analysis result for SHA-256 291c1d6756818491…

MALICIOUS

PDF

75.5 KB Created: 2021-09-07 04:07:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 83b04228f409c60aa6382661d6e1f649 SHA-1: af3eb25e92b6e575b0239217588e4094d539dbeb SHA-256: 291c1d6756818491cd203c273a6ab8aca868aba179a6b137fbc00b2b04bc632b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16076dd7cbb70b---bizozapuzawosuwu.pdf In PDF document text
    • http://azbuka-d.ru/ckfinder/userfiles/files/81154080357.pdfIn PDF document text
    • http://greenplanetnepal.com/userfiles/file/waxegisimozuvejolusok.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073b5b8ae327---8799132667.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b7d117ceec.pdfIn PDF document text
    • https://norservis.com/files/files/825222811.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1cd327955e---92406794638.pdfIn PDF document text
    • https://portugaliaimagyarok.com/ckfinder/userfiles/files/kizetebuwanulopu.pdfIn PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/1fa32f139305b45e54c010cbbae49e05/zajoweboligifavivegobalo.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/tekituw.pdfIn PDF document text
    • http://sun-eko.eu/files/file/lubofigazejama.pdfIn PDF document text
    • http://veoguidecostarica.com/ci/userfiles/files/3056499499.pdfIn PDF document text
    • https://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/7074195b07b44bdc8df9da636c3cf6cb/10129612851.pdfIn PDF document text
    • https://rcvizovice.cz/ckfinder/userfiles/files/wuvatotus.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/bisugimu.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/db97caf8c1fb048b031b437f81ccfc65/6335094885.pdfIn PDF document text
    • https://latework.cz/soubory/15814469823.pdfIn PDF document text
    • http://tao-ssct.org/data/upload/file/kigorigibuxowup.pdfIn PDF document text
    • http://imi.vc/upload/files/taxobewasuzox.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1612ceb3fab0c2---ximakotakesoleluralixuso.pdfIn PDF document text
    • http://mu-rrrc.com/userfiles/file/vesonatelexufoso.pdfIn PDF document text
    • http://studiomanzella.com/userfiles/files/7405337243.pdfIn PDF document text
    • http://mjsolankifoundation.com/fck/imagesfile/bejusafiwisigejaxu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=10+new+tamil+guide+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_off0000bfb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFB8 10716 bytes
SHA-256: 190f4ab35e0ecacfc0117568185d8b5d6a1497083d45ea30d0cc7c49fbc42dcb
font_01_sfnt_off0000d81e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD81E 18532 bytes
SHA-256: f9aaffe02ef2f5e849aee96c4b669b7ebf80ce77a73547eed30177c876ff7a4f
font_02_sfnt_off00010882.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10882 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1