Malicious PDF — malware analysis report

Static analysis result for SHA-256 8916eb590dcd1004…

MALICIOUS

PDF

87.7 KB Created: 2021-08-18 21:44:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: 906595104a579ae5fe3739ab60ce24b1 SHA-1: 0e7406837adbeb22b8cd04bbe8b4cdb09fde1fa4 SHA-256: 8916eb590dcd1004122d80200a5930c555093a712f4d7d2d0af7516557e8761b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to other PDF files hosted on compromised WordPress sites, indicating a link farm or SEO poisoning tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to distribute malware or phishing content. While no scripts were directly extracted, the nature of the links and the detection results point towards a malicious document delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9886

Heuristics 6

  • 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.
  • 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://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/psath8geo8cfh4tncoadgcjp0u/54199927693.pdf In PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd816d7f34---lexonutisifuvog.pdfIn PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/o2b4uapoenn8dk1hqk0ek4uo3m/wofawal.pdfIn PDF document text
    • http://www.ks-zahnarztpraxis.de/upload/files/wipugikijaroxawelib.pdfIn PDF document text
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/647d3f2f4a38a8245a5b7f009d809583/53418894199.pdfIn PDF document text
    • https://europacreativaeuskadi.eu/files/galeria/files/fevewoworejosesagojefu.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160733f0388f5e---lowerina.pdfIn PDF document text
    • http://emilymillerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50946135278.pdfIn PDF document text
    • https://imihwa.com/uploads/image/20210803/files/20210803033135.pdfIn PDF document text
    • http://seamacros.com/upload/file/28707327191.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/160a2e42c169fc---2692381737.pdfIn PDF document text
    • https://jgmurphy.com/wp-content/plugins/super-forms/uploads/php/files/ecdbe5d535735fbea032cd89c64a8b2b/39812874720.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/wumiwojebifuwulu.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/43inqdbalp2ab0298aehsn4c19/manekameju.pdfIn PDF document text
    • https://webshopplus.nl/app/webroot/files/userfiles/files/tajux.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/f93426ba418d92e37f52be29d1f0071b/jesanifoxitirawu.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/af790f3884e8cee75abbd8b090af9d69/94887597201.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607371e046519---duxabexobujaxisiromep.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072a1e0180d8---telot.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607007d5aa596---96789987995.pdfIn PDF document text
    • http://hyundainhapkhau.net/upload/files/13190310744.pdfIn PDF document text
    • http://www.39koratmachinery.com/file_upload/files/26384915024.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/3163035274.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160fdd87ddb86c---65330600922.pdfIn PDF document text
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/84224a7c2f65b1f853831a7ba8551def/6735557388.pdfIn PDF document text
    • http://cctechlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fupusularo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=madalin+stunt+cars+2+unblocked+games+44PDF 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_off0000e9d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9D6 19588 bytes
SHA-256: 4ab190963a7e69546c066676756e848c021198810eb0f43179bc0e00e2cebd8e
font_01_sfnt_off00011d31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D31 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013548.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13548 11236 bytes
SHA-256: c43b8aae753e28d58326be33517039b417700c111a3ce19852b319cc704566af