Malicious PDF — malware analysis report

Static analysis result for SHA-256 8829103e4c49e7af…

MALICIOUS

PDF

78.4 KB Created: 2021-09-05 22:49:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a4514cd604628c924bb18dd9b7ddddca SHA-1: a4540f964db993292e806b974bd3ae3f786a8763 SHA-256: 8829103e4c49e7aff56fedb3ad989799f08e0c049b54d2f93659fc9c8b0b03e2
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous external links, many pointing to compromised WordPress uploads and disposable hosting, forming a link farm. An embedded JavaScript stream was also detected, suggesting potential malicious scripting activity within the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/mkh7s5idntru0goaa3fjjvj2vv/tolipifizexozokote.pdf
    • https://noticky.net/akce/fotky/file/65068879828.pdf
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/nazogidegepe.pdf
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/161147975a9743---83536422513.pdf
    • https://sayurhijau.com/contents//files/78511453526.pdf
    • https://kultmotor.hu/images/files/konagazuramejemabarur.pdf
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/runuzevosazedifajekonobu.pdf
    • http://thucancakoihikari.com/luutru/files/zibisowufepilosala.pdf
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/751a374756c690c0389189dfffb0a043/95055392500.pdf
    • https://eminencesolutions.in/resources/userfiles/file/kuzep.pdf
    • http://altinay-law.com/images/file/xasiwajepi.pdf
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612399869bd74---rusegelotoxokexu.pdf
    • http://nt-module.ru/ckfinder/userfiles/files/segipuwidid.pdf
    • http://langeline.com/ckeditor/upload/files/sozopifojam.pdf
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607abd2b3dff0---12865228235.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16076263433cc0---68798214269.pdf
    • http://sasmedm.com/www/js/ckfinder/userfiles/files/77961715243.pdf
    • http://choinka4x4.org/cms/files/file/filaxulipugobudosasax.pdf
    • https://www.hippocratio.gr/ckfinder/userfiles/files/xibojubawu.pdf
    • http://montazerangroup.com/uploader/file/soduke.pdf
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/d831c689a8f1b65cab1468ce1bbdd0bd/71812383901.pdf
    • https://batikatravels.com/userfiles/file/97494699095.pdf
    • http://www.bc-arman.kz/ckfinder/userfiles/files/51631030499.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161277f993eda1---45519673713.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+combine+pdfs+without+software
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cc22.bin
d699d846e65b573ee5c6b0fe326c0c3d0739c4100d5f3ada4ea05e95d0ceaa74
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC22 17752 bytes
font_01_sfnt_off0000fa16.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA16 16792 bytes
font_02_sfnt_off0001122d.bin
f2a082d21bafc93d07b080137a7987c54a31b300ccad793a62d37d26776c9784
pdf-font-stream PDF embedded font (sfnt) at offset 0x1122D 11156 bytes