Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bb68a5c6dc6891a…

MALICIOUS

PDF

88.7 KB Created: 2021-06-30 20:34:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: c50b3b8cbb562e0ffdb0de33a3256c45 SHA-1: 852d09bb867b035cc712d0b87f4fa0e60372ac32 SHA-256: 8bb68a5c6dc6891af4049112fe28172853fce5c7e9891f0b39a36e90479d7822
96 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to compromised WordPress sites, indicating a link farm or SEO poisoning attack. The ML classifier strongly flagged this PDF as malicious. No scripts were extracted, but the structure and URL patterns suggest the document's primary purpose is to redirect users to potentially malicious or manipulated content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/375ddbd2ee3f2a64d7ce8d81b69ca8ec/92052341018.pdf In PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160848ccd4530c---96753913137.pdfIn PDF document text
    • http://allasclub.com/campannas/file/74152211263.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/abe037dff5723533178e58beb6ed2ae9/zexoboniwe.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f71d86b80b---litare.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc1af38878---51789639769.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/j9tr4d7tu1hh6r5bgqldlaamce/pepiluwusonoxe.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b47a2e61b68---41212863416.pdfIn PDF document text
    • https://himalayanwanderer.com/himalayan/userfiles/files/fotajevemizup.pdfIn PDF document text
    • http://ndt-tl.ru/upload/file/8212911856.pdfIn PDF document text
    • https://ksuskalology.com/images/file/68074027975.pdfIn PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/8otbe4lha49ulueau6gkpgk9pk/tebuzataza.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/160960e15ed79a---nukegasejo.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///52883499454.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/3343e0584a342b3430b436858dd43ab2/gotarosurovavin.pdfIn PDF document text
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/ukuimamit9fc6p8ccibeqoo1r4/79741268524.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/d27143ffa32533c1130f3419c7ce874a/55559752957.pdfIn PDF document text
    • https://twr1115.net/files/fckeditor/file/zosepimizuv.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7866a97d9---28191612976.pdfIn PDF document text
    • https://vayamcs.com/content_files/files/11014409281.pdfIn PDF document text
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5b50674f81---55596117108.pdfIn PDF document text
    • https://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/1d8b3b01a0d4381b3187ffd7ad6a293c/foruj.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607a43be27e99---85259759351.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=3+letter+words+ending+with+pPDF 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_off0000f6b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6B8 10672 bytes
SHA-256: fabc8fb2d1f31c857ce8796ae6f04137db65625d7a3b3e21eb99a0c1ecda1aef
font_01_sfnt_off00010eec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EEC 17808 bytes
SHA-256: 1d5399daf8827ecd1f1a6d33132039772c75973327218c532ebaef9021ded215
font_02_sfnt_off00013dad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DAD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1