Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c4fa164e8921637…

MALICIOUS

PDF

80.2 KB Created: 2021-07-01 14:47:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ad4014f9961680f6d9ba0572713d403e SHA-1: 12619157edac51c3032bdd48df8a755086ce0b07 SHA-256: 6c4fa164e8921637652422d2558e56601800ac177c54eef2069da396930a8193
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document contains a link farm pointing to multiple compromised WordPress sites, likely intended to host malicious files. The ML classifier strongly indicated maliciousness, and the presence of numerous external URIs suggests an attempt to redirect users to potentially harmful content. No scripts were extracted, but the overall structure points to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16089a68814ad5---miboxadewubiraligid.pdf In PDF document text
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/sf3ogmr6rbboviiiim7p6350bi/75738485659.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c39b0b6f323---49395151327.pdfIn PDF document text
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083499e8a9fc---93598404674.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/a396c91ca068d66da15e77a41be5ee9b/11470423899.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/febasopalejosixirusi.pdfIn PDF document text
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/kt7p2q4kdpl7tv46tq1v31a0oe/6830578778.pdfIn PDF document text
    • http://toshiteriyakiburien.com/uploads/files/sodurubididetore.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/f12aba8cf1496c35d93a3ceaa38221ba/38409513112.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca093711ef---purubeki.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1608c3c1c28cb7---53197062719.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5a16f11ff9---25162421395.pdfIn PDF document text
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/tazejinoko.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160789d018964f---dezawukofoxikof.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c078b0138---lerodovasipavokilopipul.pdfIn PDF document text
    • http://slippersymposium.com/clients/875641/File/zumibaginewofuz.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160afda4e8556e---larukasurelu.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1609cdc7de1378---rotelekatokadawi.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608446b67dc51---rizebezuta.pdfIn PDF document text
    • http://bhhangkhong.com/upload/images/files/mupoduvuwumanofesukon.pdfIn PDF document text
    • https://daleplumbinginc.com/wp-content/plugins/super-forms/uploads/php/files/a317c623618fbd4846a1a97ae8907fbe/wureni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=frozen+coloring+printablePDF 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_off0000d7f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7F7 16824 bytes
SHA-256: e1bbb6a4157319fe708494835513e14542a6e377becfc89457a1beafe6ed61dd
font_01_sfnt_off000103e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bfa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BFA 10560 bytes
SHA-256: 93c80090d57a908b4d20412dc688edbb8ea68fda751216274c242da5107893d6