Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2390a0112fe1feb…

MALICIOUS

PDF

70.1 KB Created: 2021-10-04 07:07:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 36abf14ffd1f6541a095137daf3f3334 SHA-1: 0aa2e5d3c1e25a2af1a535ea73ee46eec90a191a SHA-256: a2390a0112fe1feb3bab479d9f97146ce8d0bc557c75195bbe4764f4a81fb40f
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm for SEO manipulation or to distribute further malicious content. The ML classifier strongly indicated maliciousness, and the structure aligns with techniques used to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://wastran.ru/uplcv?utm_term=themes+of+contemporary+art+4th+edition+pdf PDF link annotation
    • http://gesundimjob.at/images/content/files/96959163943.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161531878a6caf---solugij.pdfIn PDF document text
    • http://www.ih-consultant.com/ckfinder/userfiles/files/jeriwadefikokoxexafanivej.pdfIn PDF document text
    • http://bc-arman.kz/ckfinder/userfiles/files/taxamojuretiwivipalivu.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/161339a4150401---wimub.pdfIn PDF document text
    • http://cartopack.com/Images/file/fodevonuremafiju.pdfIn PDF document text
    • http://makinsushi.com/uploads/files/pozawurezakugut.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/lifodumoteg.pdfIn PDF document text
    • http://sbsedupatti.com/sbsedupatti/userfiles/file/kuvidel.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/7ee327a34e208646cacb1be32af10c1a/pujitikorukuxaputupef.pdfIn PDF document text
    • http://rimini-portal.de/bilderarchiv/file/tekid.pdfIn PDF document text
    • http://guidesdugrandlarge.fr/images/import/file/52957192454.pdfIn PDF document text
    • https://chongtham68.com/app/webroot/uploads/files/sagavivibimot.pdfIn PDF document text
    • http://shanghaicruiseparty.com/uploads/file/diniba.pdfIn PDF document text
    • http://jucal.es/images/file/sedanaledodevatajojok.pdfIn PDF document text
    • http://senvietsystem.com/ckeditor/upload/files/74360374403.pdfIn PDF document text
    • https://pt-lb1.pasarantogel.com/contents/files/lubitokulegusezana.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16140e17581d6c---kobarimipukof.pdfIn PDF document text
    • https://seerupit.dk/assens/file/28417204845.pdfIn PDF document text
    • http://esistore.de/userfiles/file/wovugojobilitejatogivi.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/161389efadf284---72836938492.pdfIn PDF document text
    • http://1night2day.com/UserFiles/file/2893638302.pdfIn PDF document text
    • http://eurosolar.cz/res/file/8517406112.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b293.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB293 10992 bytes
SHA-256: 9ebbd68187948b926761649906d217bfc30fdb705a9c36249ba085740340300e
font_01_sfnt_off0000cc01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC01 15152 bytes
SHA-256: 930262eb58d769f536889dd2f24e9697a21f1bf951da76b49ee51474172ffbb0
font_02_sfnt_off0000f230.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF230 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1