Malicious PDF — malware analysis report

Static analysis result for SHA-256 053a859169c83465…

MALICIOUS

PDF

82.3 KB Created: 2021-09-07 17:54:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 572b4a893d164c0d97d4dfefda59a173 SHA-1: 7044f2a531b190cc29e071807f77e0f53bfa5383 SHA-256: 053a859169c834654cf53374e2b7a56241210918b9c363532756f76625fe85ed
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS upload directories. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm on disposable hosting, and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' confirms links to compromised WordPress uploads. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/8e6f1d8f8e541ed1431e2a2e5f41ec6a/87058206210.pdf In PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/4ab0736ff869db694abc23a649ff258c/60176892182.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/pehorjj46idbbomk2470kv2s67/dokinogakofiwujefetep.pdfIn PDF document text
    • http://xn--42c1dhzaq5aeb.com/userfiles/files/kelogipeladek.pdfIn PDF document text
    • http://championsview.net/userimages/bogebimi.pdfIn PDF document text
    • https://poldercuptrofee.nl/site/admin/ckfinder/userfilesfiles/46732836846.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/458fhnhrhheduqs92k9271vkb6/visokitorerebugakepagu.pdfIn PDF document text
    • http://boldino-hotel.com/ckfinder/userfiles/files/76574114118.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-5-25/20210525192549676953.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16125c1f6243d0---22624802947.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/k9a1c46rq76ofprvigs3c23ho3/fidaxifeme.pdfIn PDF document text
    • http://allseasonsart.com/uploads/fck_uploads/file/mawupevawoje.pdfIn PDF document text
    • https://tourpon.kr/FileData/ckfinder/files/20210829_906487C2D9F35499.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a34f0117073---37627367366.pdfIn PDF document text
    • https://cornwallstaffagency.com/userfiles/file/2026349632.pdfIn PDF document text
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/ob03fh9ika9cssaemcfqe4hj9j/xibupajitanowugedebemiwus.pdfIn PDF document text
    • https://hideab.se/tc/Mediagalleri/file/jesirosafivezebajigonedox.pdfIn PDF document text
    • http://ozanatalan.com/iboard/includes/userfiles/files/mebazoleraxavefuvodezejof.pdfIn PDF document text
    • http://toyotarent.hk/FileData/ckfinder/files/20210726_0E9FD9EF8BB17CA8.pdfIn PDF document text
    • http://thesprotia.gr/uploads/file/46941405855.pdfIn PDF document text
    • https://ancoraeducacion.com/images/xilubupowojiwowu.pdfIn PDF document text
    • https://die-elke.de/cms/elke_page_files/file/26243545322.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/tnnhhg0oemscvbbfv83ph7turp/45225019010.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/7f232fb62cd3359eb1304ca5c4e9e936/dodajebivodeputorofose.pdfIn PDF document text
    • http://geopraxis.it/userfiles/files/lefolaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=walk+in+interview+in+noida+for+manual+testingPDF 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_off0000dace.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDACE 18264 bytes
SHA-256: 92427cb1830d3f89c4f1fe26f23cc4a1d82231a91dc836f8da5cd54c480352ad
font_01_sfnt_off00010a48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A48 11036 bytes
SHA-256: 9d1520b71833a27b0276bdf38a192e5be6926390ed0aa911ad1db3607418f97b
font_02_sfnt_off000123c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123C8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1