Malicious PDF — malware analysis report

Static analysis result for SHA-256 fdbfd4fb2d4a2715…

MALICIOUS

PDF

83.2 KB Created: 2021-06-25 22:22:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b6aabdc85f9321296a2d265f3efde9c4 SHA-1: fb32da8e18b962e6727b78879784d027b0b9d93f SHA-256: fdbfd4fb2d4a2715238eb06fa3a7d8ef926576e608485271345267a39e5070f4
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links pointing to compromised WordPress sites, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the structure and numerous external links suggest an attempt to direct users to potentially malicious content or phishing sites, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/d5faf114d908ad9f9470626257ef3750/25222464324.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607562dd88d2a---47687733569.pdf
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085ed014c9ac---nipakoxogaberatu.pdf
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16076843e40ea9---derudapuzadinevubow.pdf
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ed033ac540---xolotipasepabofipemaped.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16078e164a69fc---vixatopazetogivuvorap.pdf
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fe646a4d2c---rogupi.pdf
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/rdqn8u1dds98aa54rme9i0sor0/13145719961.pdf
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160c3a9f303450---wigovidus.pdf
    • http://cloverpark1961.com/clients/6/6a/6a73a08bb68f643008adb5efbbb44e43/File/21303810742.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160869258e1e77---74688072111.pdf
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/4ebf52bf856d62150ad4dba5460dc434/43979044760.pdf
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/9450595cc6fee135e805ae5a0c7dc3f1/jikepuzofiriribolotinan.pdf
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/9812f623f73c177b0a2d9856a02a7c7c/tatugujixomogipusonosug.pdf
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091377c25561---mudapisisevag.pdf
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/c7eeb5fc52dbd72d71a939cd09d9f6c8/lokipanewufusabawemotosof.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/0eptnphk9nuotabcpivuder732/55260365241.pdf
    • http://auto-spec.ca/fck/file/vonigiraji.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=how+many+calories+in+cooked+red+rice
    • 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_off0000e3d7.bin
9c4ed0115e50fef9fc45e397015d106e796268d6cbc3cc1c06b23e922315e376
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3D7 10716 bytes
font_01_sfnt_off0000fc6e.bin
1aa22b5c1d0d7aa810a3a85242063a54a6b4f8561320870f26b2cd86accc19fc
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC6E 16760 bytes
font_02_sfnt_off000127f8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x127F8 16792 bytes