Malicious PDF — malware analysis report

Static analysis result for SHA-256 c954f21b3129816c…

MALICIOUS

PDF

80.7 KB Created: 2021-09-15 14:11:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1e3f30c5ba6d94d72f75600b2d7105d4 SHA-1: 3dd410c71637b69a431cd45436af6ed5fae73dd1 SHA-256: c954f21b3129816ca2d27a102d331ec111fdaa9be91e7c18dc71572ae12621ca
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for exploiting vulnerabilities or redirecting users. Multiple heuristics indicate the PDF is part of a link farm, with many URLs pointing to compromised WordPress sites or disposable hosting, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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 http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9141d9d7b---vebikivuzupo.pdf In PDF document text
    • http://stlukesfp.org/ckfinder/userfiles/files/71812945403.pdfIn PDF document text
    • http://pappteam.hu/userfiles/file/88372246754.pdfIn PDF document text
    • http://sabancilojistik.com/userfiles/file/butogovegal.pdfIn PDF document text
    • https://giaynangchieucao.com/userfiles/file/1794541014.pdfIn PDF document text
    • http://fitnessklub-impuls.pl/uploads/assets/file/dowiposekisar.pdfIn PDF document text
    • https://guijek.com/userfiles/file/10291644351.pdfIn PDF document text
    • https://alajuusa.ee/media/contents/file/topixesezujarera.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/o0bbtkhbgcgrf73vrb9ovgu7a0/26663225884.pdfIn PDF document text
    • http://abogadosaguilar.com/ckfinder/userfiles/files/wivutuxirixejalikira.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/vubifakak.pdfIn PDF document text
    • https://www.stock2morrow.com/ckfinder/userfiles/files/43948571897.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/xilegamenigunetud.pdfIn PDF document text
    • https://krainaogrodow.eu/zdjecia/fck/file/siweluxobesof.pdfIn PDF document text
    • http://mothertheresapublicschool.com/userfiles/file/4499627461.pdfIn PDF document text
    • http://pastadimatteo.com/ckfinder/userfiles/files/dijamirenabegigekinazof.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613142ca6a46e---koviwi.pdfIn PDF document text
    • http://ncteonline.com/userfiles/file/69837354230.pdfIn PDF document text
    • http://jongauger.com/userfiles/file/xajugojobefulenovozesixu.pdfIn PDF document text
    • http://fuyu.010bi.com/ckfinder/userfiles/files/99164926461.pdfIn PDF document text
    • https://onutglen.com/caningest/images/file/xedibalorefelurowas.pdfIn PDF document text
    • http://xn--80aamwn.xn--p1ai/userfiles/file/66763474998.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=ace+stream+media+androidPDF 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_off0000d700.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD700 17628 bytes
SHA-256: 8d4bd5be129d72e5edcc8df5a8c9cbba3400b1a170fcd5233404c2419606ba14
font_01_sfnt_off000103f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103F1 10468 bytes
SHA-256: e156ee4cebebe0317a335aa83e5e5f418bfa4aad30265baec4619b2a6176b81c
font_02_sfnt_off00011bc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1