Malicious PDF — malware analysis report

Static analysis result for SHA-256 c43af375db156b35…

MALICIOUS

PDF

194.9 KB Created: 2021-09-08 04:06:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 24f15b920719cf6b338bad59cd98e934 SHA-1: 6fbfe9c07e198ca2e47fbf1e5bc4f7f38af28972 SHA-256: c43af375db156b357398424ed5aa85c1b46b6bff6a363f17a3adc8850c9fa733
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9863

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/59e7b531e84c76c3765ce56928bc368a/78953758891.pdf In PDF document text
    • https://akrmedia.no/ckfinder/userfiles/files/kuzojinotebikozozed.pdfIn PDF document text
    • http://9jamail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/88067901638.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/kovatowopup.pdfIn PDF document text
    • http://alfadent-volg.ru/images_uploads/files/40651350051.pdfIn PDF document text
    • http://www.leads-bd.org/app/webroot/js/ckfinder/userfiles/files/92025248212.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a0eb8430003---92569514157.pdfIn PDF document text
    • http://yves-segers.be/userfiles/files/jogugiv.pdfIn PDF document text
    • http://massarentearchitettura.com/userfiles/files/rolalejidusute.pdfIn PDF document text
    • http://afgventuregroup.com/cfiles/file/kepobewonirike.pdfIn PDF document text
    • http://xn--80aagkbrca3apkgkee0a1bi.xn--p1ai/ckfinder/userfiles/files/55203521560.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/1276020430.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/1609718fde83cc---61625997348.pdfIn PDF document text
    • https://willmarlakesarea2040.com/ckfinder/userfiles/files/guranedozogufub.pdfIn PDF document text
    • https://www.cascatai.com.br/ckfinder/userfiles/files/42410862669.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610beaab4ea19---24026018706.pdfIn PDF document text
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/akflvtagb28va3i89dbtfb3brh/mojojiruxebufe.pdfIn PDF document text
    • http://stagelight.pl/userfiles/files/polobasefivefi.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a6773940989---12885531722.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0fdd7fb0f---50683147531.pdfIn PDF document text
    • http://theheavent.com/userfiles/files/sivotomibisefu.pdfIn PDF document text
    • http://bpsstudio.hu/uploads/bezenakujokaviru.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/a8ad92da6a0e704dfa55db822d8e0685/kaponimaxumuzifiteto.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c50f2597b52---21229665391.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607698619cdb3---zusuvusozejakevoxafinawe.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/44315a8d64f032d526c48dc1d609a97a/89893092731.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=partituras+para+banda+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_off00029888.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x29888 10436 bytes
SHA-256: b86ee555a41c7f8a926da002bf086090ccf0e1016bf5081da7bbd2c308a765ec
font_01_sfnt_off0002b003.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2B003 21476 bytes
SHA-256: fc6a822b31f7f98897b1a76f8082ac3f27073a1f5c88b3c24d9ec59ad33ed0c2
font_02_sfnt_off0002e54d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2E54D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1