Malicious PDF — malware analysis report

Static analysis result for SHA-256 71d11b381e449bf7…

MALICIOUS

PDF

86.2 KB Created: 2021-07-07 13:57:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7d1c4ca81c49a82f4d8ce39b32029ada SHA-1: 6a436c79a3a8282e77f7c944fc2f941ba63c7187 SHA-256: 71d11b381e449bf7ab75810d87a772a7cef92b8a4a509c6d0d172513826b3b40
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload directories, suggesting it's designed to lead users to malicious content or phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution through these links. No scripts were extracted, but the PDF structure itself is used to host a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://irlanc.ru/uplcv?utm_term=how+much+daylight+do+chickens+need+to+lay+eggs
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/m7apclinck4gv2vsn5ebimeaen/3690950497.pdf
    • http://bet-balance.com/userfiles/file/vivogaxonokukomadad.pdf
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160b6652ae2b39---vuwipogidetumotebitev.pdf
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074181e33dc4---mizezaxavirodejabafusove.pdf
    • http://donghocasiochinhhang.net/uploads/userfiles/file/19173321033.pdf
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/gj4h6i8andutjvhrsf5ia3f5b6/76065473123.pdf
    • https://sardavetri.it/userfiles/file/39917394453.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160803b239f2ec---zajagukuluj.pdf
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/0114b6c69264235ebad092ba5e2ea8a5/41177229867.pdf
    • https://luyenthitoeic.info/userfiles/file/22734008086.pdf
    • http://mynigaoe.com/upload/file/20210531210537.pdf
    • http://aedelsur.com/contenido/files/nununok.pdf
    • http://thessalonikiflights.com/files/files/riroxet.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/09721f31598b6804c1af5b1eb3dc768b/xonevujedin.pdf
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/3ephi713psckg0c5617ls9j5g5/68852141718.pdf
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a65da68638d---64539359246.pdf
    • http://pechati-piter.ru/userfiles/file/sifexe.pdf
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f2d32ea316---70887533589.pdf
    • http://forresterfamilyreunion.com/clients/c/cc/cc72bfd2512333311cc1ef5a4fdef90f/File/12653800435.pdf
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b9b85ae0b46---sagaletid.pdf
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/0f77ed02347ab0002e61152107022c0e/paduzomulomogak.pdf
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/v8vam7mv17pdg2hsfpmgalu803/34435909008.pdf
    • https://eqonetech.com/upload/userfiles/files/67151647973.pdf
    • http://solamsys.com/userData/board/file/gozigujamorivurikuz.pdf
    • https://tenfci.org/userfiles/file/37425386617.pdf
    • 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_off0000ed88.bin
8c3908c0cde538f7a770e767891e42568e9c66c29331e22999d7f732d6016710
pdf-font-stream PDF embedded font (sfnt) at offset 0xED88 17044 bytes
font_01_sfnt_off00011a0a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A0A 16792 bytes
font_02_sfnt_off00013221.bin
1d49d66ecb6f2c1a8abaa09a09d7750334b4ffe70248eda6a6203275dec752cd
pdf-font-stream PDF embedded font (sfnt) at offset 0x13221 11100 bytes