Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdc7c4f30d87457a…

MALICIOUS

PDF

91.2 KB Created: 2021-09-21 23:25:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 901ba9e4d0989527c48feb846f811573 SHA-1: 29ad1f3af79d9f35a1d8efb0f924a19050b7b961 SHA-256: cdc7c4f30d87457a94cba4a907de5cdba57df42fd2040f2d8c56ee64fac143d4
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to other PDF files, many hosted on compromised WordPress sites. This behavior is indicative of a link farm, potentially used for SEO manipulation or to distribute further malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/e253daae2dcc3384ed9933dcace63b97/12359305915.pdf In PDF document text
    • http://boxerdapolenta.com/cmsimple/images/file/rafotosikoju.pdfIn PDF document text
    • https://frontivo.ro/userfiles/file/jugopenawikapafunufuxake.pdfIn PDF document text
    • https://daulte.ch/ckfinder/userfiles/files/47627915612.pdfIn PDF document text
    • http://nincity.de/inline/file/96743923818.pdfIn PDF document text
    • http://imcborivali.org/userfiles/file/15155843405.pdfIn PDF document text
    • http://vwtint.com/userData/board/file/loboripagomafike.pdfIn PDF document text
    • http://diegogenna.it/userfiles/files/sazoriroxab.pdfIn PDF document text
    • http://bradzo-ep.com/uploads/files/63848248526.pdfIn PDF document text
    • http://xn--939a66v0zjo3bcvdmrp.com/data/ckfinder/files/pesozeboxujobajidaxu.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/b7ef74334589706926bf55394987a6e4/savosoju.pdfIn PDF document text
    • http://xsteelstock.com/d/files/37396724156.pdfIn PDF document text
    • https://dcimx.com/files/92466268242.pdfIn PDF document text
    • http://allivecoat.com/userData/board/file/rolol.pdfIn PDF document text
    • https://vcubusinesssolutions.com/userfiles/file/baligutopewuwodadavik.pdfIn PDF document text
    • http://firewaterdamagedfw.com/test/fckeditor/uploadfiles/file/ximojobolufelira.pdfIn PDF document text
    • https://allianztc.ro/files/file/zerazofibaduselemeturovo.pdfIn PDF document text
    • https://doctmcooper.com/userfiles/files/fulosekojulud.pdfIn PDF document text
    • http://eca.or.th/ckfinder/userfiles/files/wabuxolojoduxosa.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/161442988b554c---jejegonifazubarevuzek.pdfIn PDF document text
    • http://wideanglepackaging.com/ckfinder/userfiles/files/55021204644.pdfIn PDF document text
    • http://www.neoneofitou.com/ckfinder/userfiles/files/2877473512.pdfIn PDF document text
    • http://www.dr.schure.net/ckfinder/userfiles/files/dizomesujigapoxavutukep.pdfIn PDF document text
    • http://shriadinathbank.com/uploads/xorogobusibitusipokemab.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148df7e4a5a1---liralawabomizirerile.pdfIn PDF document text
    • http://kustari.net/userfiles/file/95499001169.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=fifa+online+4+mobile+english+apkPDF 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_off0000fcf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCF2 10896 bytes
SHA-256: f146118e9c9097b0e5d1bc13efbf90279d17ec8e36d61328ee2db5cee7c9f935
font_01_sfnt_off000115b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115B1 19116 bytes
SHA-256: 0835f0481b680762b01fb7854818d7627c17e9d3110f0320531fce0de7279f4e
font_02_sfnt_off0001478e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1478E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1