Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8a7d84a5dd93588…

MALICIOUS

PDF

98.9 KB Created: 2021-09-13 06:10:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 193c152dc3e2a46e7ec8bbc180a8bb4e SHA-1: 05c87e89e501e0bd509f1623b6c8501048b90fe1 SHA-256: b8a7d84a5dd93588ffbe16b20322f3699b5a0753cf07f1d92ed392dd4f291613
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are part of a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://philabc.ru/uplcv?utm_term=brokeback+mountain+by+annie+proulx+pdf PDF link annotation
    • http://eros-arena.name/eros/userfiles/file/vumexaduwaxix.pdfIn PDF document text
    • https://kiptep.ru/file/44604217218.pdfIn PDF document text
    • https://stockbauer.hu/uploads/file/tarugixevepi.pdfIn PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/zarefametoxuk.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc8f988f72---37102512079.pdfIn PDF document text
    • https://arendic.cl/files/govunulalux.pdfIn PDF document text
    • http://anadolumatbaa42.com/genelresimler/file/lasogifufuk.pdfIn PDF document text
    • https://xn--hjrnskadeakademien-mtb.se/userfiles/file/vopuwositejitiwugig.pdfIn PDF document text
    • https://halkapsikoloji.net/userfiles/file/53290111958.pdfIn PDF document text
    • http://e-park.es/img/uploads/files/70073734012.pdfIn PDF document text
    • http://vektor-bezpeki.com/userfiles/files/2996881540.pdfIn PDF document text
    • http://hoaisonland.vn/upload/files/zuwusunutiludubis.pdfIn PDF document text
    • http://pallenberg-busreisen.de/uploads/files/befete.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/44f9eb8a6031f5f11eb3a4abfe8698f8/87955820290.pdfIn PDF document text
    • http://rw-hse-businessconsulting.de/userfiles/file/98037736719.pdfIn PDF document text
    • https://octvads.site/js/ckfinder/userfiles/files/26531403515.pdfIn PDF document text
    • https://cpsguffanti.com/uploads/file/98434489654.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612ffa24bdcf2---kesoxapowefema.pdfIn PDF document text
    • http://rts-3.ru/upload/files/91548189272.pdfIn PDF document text
    • http://denetimmusavirlik.com/userfiles/file/zatajeluxijadaxalige.pdfIn PDF document text
    • https://rusepress.com/uploads/wysiwyg/files/furolisavow.pdfIn PDF document text
    • http://xyr59.com/filespath/files/20210912025029.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_off000113f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113F6 11212 bytes
SHA-256: 6d1a635017ddf26d0e45c0d2521307f4d20a21069e83c7f2db0768298ddb468b
font_01_sfnt_off00012e0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E0D 21536 bytes
SHA-256: 46f12de605482776cb5bf70ef26230aa679a7e370ee65dc6ca56aac4dee6668e
font_02_sfnt_off000165cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x165CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1