Malicious PDF — malware analysis report

Static analysis result for SHA-256 9867e6f356f610b7…

MALICIOUS

PDF

87.8 KB Created: 2021-07-03 09:12:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 309770390a0c5fecb6c7e6c5015c33ec SHA-1: 8ab3dc4677306ff70f8f8cca94cd82a8c45d8227 SHA-256: 9867e6f356f610b71ea80385bbcacf32fdd98af163d4ee6e7de0a35ee8e21c93
96 Risk Score

Malware Insights

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

The PDF file contains a large number of links, many of which point to compromised WordPress upload directories on various domains. The ML classifier strongly indicated maliciousness, and the link farm structure suggests an attempt to manipulate search engine results or redirect users to malicious sites. No scripts were extracted, but the primary attack pattern is the distribution of malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/25ed0a01c6dbec842a9e3d44d03de157/73215074640.pdf
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/deh2cvfvarmutbkv8tci89nnc6/55956160567.pdf
    • http://cuatudongsaigon.vn/uploads/files/58864044571.pdf
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608147c467992---moxemisejol.pdf
    • http://blueyee.com/upload/file/141046245882.pdf
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/62117c0b428a338a1c99c5191eb0ed0e/lamajupomajum.pdf
    • http://fixafilm.se/userfiles/file/24079922325.pdf
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606cfe0458c82---75187407979.pdf
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/89b7c2985e066a8625a251623a9d76f1/11788977896.pdf
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/qokp2u1lp6kqp690c6elir24c4/75686130062.pdf
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160d60f785ab00---wawaxipijireni.pdf
    • http://erfaspot.com/resimler/files/3709442991.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/6c5f1ce319a7999141d30f6cc7fbcc5d/lanolojelapuruwozobeta.pdf
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab0f914cc25---wokesarepuluruk.pdf
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090ad5207b1c---zoxogadulijugukevixurumu.pdf
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/o4e8f89t08b573c5eqm2ha120f/55640153260.pdf
    • http://xlsferrosilicon.com/d/files/baxaxotite.pdf
    • https://masihpt1.com/contents//files/sakanedufinaka.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608b2f749a8d3---22800043205.pdf
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b896c1974a6---gasutofowusifitowidimero.pdf
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/kh12m47nreqgud6a7jgegtjeeb/43463108177.pdf
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fe7f029e3b---wedog.pdf
    • https://soechi.net/userfiles/file/mizap.pdf
    • http://gabinetortodontyczny.eu/userfiles/file/peginebonegumob.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=my+sentiments+exactly+meaning
    • 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_off0000ed73.bin
cd4b823666f0d776b9d3bfa99108a6e45ec8b4eed980ef52505c061a7fdf3bc8
pdf-font-stream PDF embedded font (sfnt) at offset 0xED73 10560 bytes
font_01_sfnt_off0001058e.bin
cadc01e60b706af8243c46c8807fd5373354a5bbe3a34ecf2e274d349e258fed
pdf-font-stream PDF embedded font (sfnt) at offset 0x1058E 19404 bytes
font_02_sfnt_off00013834.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13834 16792 bytes