Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9d8e75cf54c2a5e…

MALICIOUS

PDF

73.8 KB Created: 2021-09-24 19:25:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 218376bbb2e3bb99fa9c146fc18df720 SHA-1: da76032c612cc177f0d70103c321b6bda9801d63 SHA-256: a9d8e75cf54c2a5ea0b202ac1e1a89a5ec9002620e894b9b533bd1f5dfb3ff08
104 Risk Score

Malware Insights

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

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to link farms on disposable or compromised hosting. The ML classifier strongly flagged this PDF as malicious, indicating it likely exploits vulnerabilities or attempts to redirect users to malicious sites. The presence of JavaScript suggests an attempt to execute code, potentially to download further payloads or perform other malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9939

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://laborke.ru/uplcv?utm_term=mobile+legends+bang+bang+new PDF link annotation
    • http://lncxjzxxw.com/upload_fck/file/2021-9-13/20210913020855978286.pdfIn PDF document text
    • https://virtualpulse.eu/UserFiles/file/lajutebuneruwolanifikemij.pdfIn PDF document text
    • https://conexusinternational.com/ckfinder/userfiles/file/8135836175.pdfIn PDF document text
    • http://kingswaytyres.com/project/kingsway/uploads/file/tazum.pdfIn PDF document text
    • https://nistd.in/userfiles/file/91091726049.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1614d8faa7f000---32663756670.pdfIn PDF document text
    • http://fpole.ru/sadm_files/68261496948.pdfIn PDF document text
    • https://nacionalequipamentos.com/ckeditor/uploads/files/43641347176.pdfIn PDF document text
    • https://growyourmoney.in/userfiles/files/gibefowarowenugise.pdfIn PDF document text
    • https://bluza-shop.ru/content/File/6899171651.pdfIn PDF document text
    • http://abwingsva.com/uploads/files/62186344348.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614263289d409---zefalosovuge.pdfIn PDF document text
    • http://xhslsh.gdx.cn/ckfinder/userfiles/files/44980118715.pdfIn PDF document text
    • http://kaitianjinghua.cn/admin/userfiles/file/202109170705246754.pdfIn PDF document text
    • https://nezrenpin.com/calisma2/files/uploads/didemeziwixivanawak.pdfIn PDF document text
    • http://etepi.pt/js/ckfinder/userfiles/files/95693111203.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/12151016037.pdfIn PDF document text
    • https://impactmediaresources.com/userfiles/file/raxefudutetebifepa.pdfIn PDF document text
    • https://careersourceokaloosawalton.com/files/public/fudozawupuvezeminif.pdfIn PDF document text
    • http://ineke-ott.nl/keramiek-beelden-imagesfile/12298585559.pdfIn PDF document text
    • http://taiwan-tsai.com/upload/files/zewotomawapub.pdfIn PDF document text
    • http://bugaboo-buffalo.eu/UserFiles/File/17489857416.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/16149229e12e09---50046809047.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/b968b39767921989decb1c571090c832/mapadumamerinikigogomaj.pdfIn PDF document text
    • http://abwingssuffolk2.com/uploads/files/lozunapidokuk.pdfIn PDF document text
    • https://hoavily.com/uploads/files/batujupewevogetum.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_off0000bafb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBAFB 10444 bytes
SHA-256: ec804adadafa03be8f2dfda143260b56b662011be750d84a6bbfb7505853a921
font_01_sfnt_off0000d294.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD294 18392 bytes
SHA-256: 482365d7c6a052289b76fb9af4eb9b5770699b975a16e384fdb8a065f7ab33a6
font_02_sfnt_off0001011e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1011E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1