Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ce18fc5ba87d796…

MALICIOUS

PDF

94.3 KB Created: 2021-09-03 03:28:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2aa1aa387e14a5a9bef12941d2e9a9ab SHA-1: d090820dee4cf4b1d04e2e07ce23d254a30fe007 SHA-256: 6ce18fc5ba87d796a3a63a5c6b6b1b701239f74cc897884c414c568b9018ac0e
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload directories. The ML classifier strongly indicated maliciousness. The document body is heavily obfuscated and unreadable, suggesting it's not intended for human consumption but rather to host links. The primary attack pattern observed is the use of a link farm to direct users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://vizugy.hu/uploads/files/gutufe.pdf In PDF document text
    • http://vuatoyen.com/uploads/userfiles/file/kotukoxewukinebu.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc816ea775---83573995813.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160810bb568fe9---galularimi.pdfIn PDF document text
    • https://houstoncoinshow.org/FCKeditor/file/54764366740.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/9b0b9f56361e64d2b9acc813831d3231/davupukominujipozob.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-5-12/20210512075353981586.pdfIn PDF document text
    • https://maggies-handmade.com/UserFiles/files/pebimejolerajadup.pdfIn PDF document text
    • https://weyergans-hcc.lv/userfiles/file/44430523940.pdfIn PDF document text
    • https://esportenerd.com/app/webroot/ckfinder/userfiles/files/76275578972.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1609ba5fa94536---11185669283.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/160bb8ae794a74---64634681082.pdfIn PDF document text
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/441675245a78a4254052cfca8c8e7781/xewagowog.pdfIn PDF document text
    • https://gachbinhduong.com/upload/file/53618507639.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/43d9270893fb996cf10907189a337d65/nevogite.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/40d66024fae9cbbff0137ea7a6f49125/viweturasupekakas.pdfIn PDF document text
    • http://xn--9d0b102a6wc3y4a.com/sa_upload/userfiles/file/20210522083531.pdfIn PDF document text
    • http://klubbelgickychobrov.sk/editor_uploads/files/ridodi.pdfIn PDF document text
    • https://danielstrehlau.com/userfiles/file/37626410869.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/16078b0785c70d---lolalularijiwupobujokanil.pdfIn PDF document text
    • https://venefoil.com/ckfinder/userfiles/files/65982683617.pdfIn PDF document text
    • http://oiseau-bleu-morzine.com/userfiles/file/lutulidekalolekar.pdfIn PDF document text
    • https://folklorebridge.eu/uploads/pictures/files/sinujabenagivuvevazo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=piezoelectric+ceramics+principles+and+applications+pdf+downloadPDF 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_off0001085e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1085E 18956 bytes
SHA-256: 44c53ea5ee49613b0652b319c1a4284e4c900fac042646e4bf7544e140a8f903
font_01_sfnt_off0001395f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1395F 10928 bytes
SHA-256: 79f4f5e2fdf70da7349f85e278f91d575db543cd5a66f47b6d43e4df5cf92dbf
font_02_sfnt_off000152ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x152CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1