Malicious PDF — malware analysis report

Static analysis result for SHA-256 861b7bf70a7e9321…

MALICIOUS

PDF

83.8 KB Created: 2021-08-20 02:18:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ae7ce5a359aaf39a3d1a68988cd6979e SHA-1: 09ad22c91dec46203399c51741803acb6f474660 SHA-256: 861b7bf70a7e9321f2ddfe87ef94272f25ce879bb4d9eeb57cd207b859442665
96 Risk Score

Malware Insights

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

The PDF file contains a large number of links, many of which point to compromised WordPress sites or disposable hosting. This behavior is characteristic of a link farm, often used for SEO manipulation or to distribute malicious content. The ML classifier strongly indicated maliciousness, supporting the assessment of a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.springperfect.com/upload/finder/files/finuworepowe.pdf In PDF document text
    • https://addsfly.com/userfiles/file/17606317783.pdfIn PDF document text
    • http://ridgefieldpark1967.com/clients/3/39/39eebdc8797e30ee23d4fd57d071fd44/File/bexiwatevuxojikagali.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a5197c2b137---mivuxenojetumapi.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/b23273aa84629895ad0e51525f7fc628/rulomo.pdfIn PDF document text
    • http://seoulmenu.com/uploads/files/baxufodawikifatuzaz.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609b3d4124279---69874307853.pdfIn PDF document text
    • http://kenzoum.org/home/integrity/public_html/ckfinder/userfiles/files/bazaminugetobikelabelided.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/43540035361.pdfIn PDF document text
    • http://usaoxin.com/userfiles/2021-7/file/74927786702.pdfIn PDF document text
    • https://odontologosmalca.com/images/userfiles/file/pabawiranosugujek.pdfIn PDF document text
    • https://roofmed.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607af89e56e96---97283181978.pdfIn PDF document text
    • https://big-affaires.com/img/pics/files/150968831.pdfIn PDF document text
    • http://zuche0551.com/upload/file/70620333507.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/ce5b488f1fb4950d041ebc98afe804f3/lakokebikunojevigew.pdfIn PDF document text
    • http://www.videocopilot.net/assets/public/ckfinder/userfiles/files/samibitajabarag.pdfIn PDF document text
    • http://tryinvest.eu/userfiles/files/sidafejuni.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/4o4pjjhmij4fq81t9q08n0kg90/19426693286.pdfIn PDF document text
    • https://5a.ro/ckfinder/userfiles/files/5373559038.pdfIn PDF document text
    • https://slide-bearing.com/d/files/nuzexatedutijipedefe.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/47688827749.pdfIn PDF document text
    • https://shian-jin.com/UserFiles/files/94775935737.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c15cf3ada17---75729868413.pdfIn PDF document text
    • http://tivatijapan.com/uploads/userfiles/file/rofujazop.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ccff88f4a---vuxek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+use+maschine+2+in+fl+studioPDF 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_off0000e421.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE421 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC33 16852 bytes
SHA-256: 0f9c0de61fad0c0c4b15462852960723cd2dc51c3a009c0b2a20e13f6b3efcb1
font_02_sfnt_off00012840.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12840 10936 bytes
SHA-256: f0021514a4022244fce2bcd64319d90b8e2f8947be155186a70a2803e6345913