Malicious PDF — malware analysis report

Static analysis result for SHA-256 d58c303a36398b7f…

MALICIOUS

PDF

70.2 KB Created: 2021-09-07 00:32:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 211c88f828895bbebeb148f1bb895eb7 SHA-1: dd0b5f662a7cc34c9a648057879e2ec57d6b36f2 SHA-256: d58c303a36398b7fc7660fe7702212b46434eaf7e2c71a4ca3f643f4996e146c
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains a large number of embedded URLs, many of which point to compromised CMS upload directories. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates that the document is a link farm on disposable hosting, suggesting an attempt to lure users to malicious sites. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 5

  • 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://infrive.ru/uplcv?utm_term=electricity+and+magnetism+worksheet+part+1 PDF link annotation
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160854da0dae11---71143503662.pdfIn PDF document text
    • http://www.elstar.ru/uploads/files/74950801861.pdfIn PDF document text
    • http://sakem.org/userfiles/files/99035572851.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a85938b98ea---logonavasute.pdfIn PDF document text
    • http://zoop-tech.com/ckfinder/userfiles/files/56885654470.pdfIn PDF document text
    • https://loctra.net/userfiles/file/sesiwogofefexulel.pdfIn PDF document text
    • https://bosgo.mn/uploads/files/90013277447.pdfIn PDF document text
    • http://ikhmongol.mn/ckfinder/userfiles/files/27440028212.pdfIn PDF document text
    • https://digireg.com/upload/dulivede.pdfIn PDF document text
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/86b772eb9b56f4a05bdee8da305b7817/8682090310.pdfIn PDF document text
    • http://teamtrinity.net/trinitya/file/59902824636.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160abd8b04ee90---pedefulinazemuvivudoluv.pdfIn PDF document text
    • http://osoboebludo.com/ckfinder/userfiles/files/34833355101.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/3c24d79781f2c58b2ebfbc77fb26cdd6/jivonojubuwep.pdfIn PDF document text
    • https://hogies.com/includes/template/uploads/file/jikupatudijukugawat.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/160998dcf88044---bamafabowasubiviwagukuliz.pdfIn PDF document text
    • https://korzayithalat.com/spot/admin/fckeditor/userfiles/file/xenoviman.pdfIn PDF document text
    • http://agnieszkapawlik.com/userfiles/file/mubunaxajukojuli.pdfIn PDF document text
    • https://aduanaldelvalle.com/userfiles/file/37776538564.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160effc124f14a---60278643925.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/b6ff794f0bd1370398a48342fdd2ee2b/77177763157.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_off0000b3e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3E6 11288 bytes
SHA-256: af00b0a0c18dd7a7ddd43d2a1b55f6a4d5b9ec92e5612e6a09590b40c8401ea9
font_01_sfnt_off0000ce18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE18 14884 bytes
SHA-256: 8070e77ad18d8dfc16ab5b90003bc64af961ef53b6fb576e78d2d13e92ad9577
font_02_sfnt_off0000f32f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF32F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1