Malicious PDF — malware analysis report

Static analysis result for SHA-256 23204b4b43aaa06a…

MALICIOUS

PDF

93.5 KB Created: 2021-08-11 15:15:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: b01ca29241e7e0834949a89445b2fcec SHA-1: 35a3c8e452ca689057e9655583c37b42f90e87ce SHA-256: 23204b4b43aaa06a4718d2ae930c296ef735d708816a52cbb6e107c523dede6f
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs that point to compromised websites and disposable domains, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious, and heuristics confirm it is a link farm on potentially compromised CMS uploads. No scripts were extracted, but the primary attack pattern involves luring users to external, potentially malicious, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://oniceh.ru/uplcv?utm_term=novena+ala+sangre+de+cristo+dia+3 PDF link annotation
    • http://xn--oy2b9bv81anouola.com/upload/file/202107270745393476.pdfIn PDF document text
    • https://ecobox.eng.br/wp-content/plugins/super-forms/uploads/php/files/ml6kdsr3r94jo7n0fg4s3v7630/12439056163.pdfIn PDF document text
    • http://chistogood.ru/admin/ckfinder/userfiles/files/8787235947.pdfIn PDF document text
    • https://kurek-rowery.pl/user_pict/file/fesobogamekoxerokufoxe.pdfIn PDF document text
    • http://ros-grad.ru/fck_editor_files/files/62776481243.pdfIn PDF document text
    • http://portalpr-b2b.es/img/user///file/_0373038001625622235.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/desowuvasuvimajinosegowa.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160add1a3ada67---mifasixuvisefifukuv.pdfIn PDF document text
    • https://fullmagicweekend.com/ckfinder/userfiles/files/jiguwekifux.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/90599026014.pdfIn PDF document text
    • http://vom-ragnaroek.de/uploads/file/kuzitesukedo.pdfIn PDF document text
    • https://rajakeempat.com/contents//files/47223919473.pdfIn PDF document text
    • https://nnt52.ru/userfiles/file/22703381565.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1608a9ecb21c37---30638323079.pdfIn PDF document text
    • https://designclarf.it/file/41734910202.pdfIn PDF document text
    • http://kodemari.info/data/files/37184029319.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7df232b9df---57360807710.pdfIn PDF document text
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/c271b2f47063dfd644cbb6398a1003f4/lotobolozulazunosal.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/5538e3bb148d62a4fe2b2710aba29f14/76265930051.pdfIn PDF document text
    • http://accomplishtheimpossible.com/userfiles_ati/file/gakikadurafajawozu.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e84f9205e29---85073652328.pdfIn PDF document text
    • http://profm.hu/files/file/zipekinugotaxo.pdfIn PDF document text
    • http://e1pl2.nazwa.pl/busy/fotki/file/51962421864.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_off00010b0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B0A 10760 bytes
SHA-256: ca1459916227857530f7ec452d1d359e3343d461f35c2f2f876f453804b12a2b
font_01_sfnt_off000123cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013bdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BDD 17272 bytes
SHA-256: 5eeaff20bb4d157e02953e53ceb408fed6e3f9390f3a1dd9d6167d2e4f631509