Malicious PDF — malware analysis report

Static analysis result for SHA-256 43ac267fe5e4d940…

MALICIOUS

PDF

75.2 KB Created: 2021-09-01 08:02:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2345b37a7dfefa6729f674d51d892d04 SHA-1: de45064335d3241a7d1f49a29dc1d1dccf1621a6 SHA-256: 43ac267fe5e4d940b6101d2620002d7fe6ddb88f3ab4aee6425e2537df80fd12
96 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to other PDFs hosted on compromised WordPress sites, indicating a link farm designed to distribute malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment that it is part of a distribution scheme. The presence of multiple distinct hosts and the use of 'utm_term' parameters suggest an attempt at SEO poisoning or a similar tactic to attract victims.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/853c4927d7f85a8a5df88fa4f091db5e/gagulezosezogebifonedet.pdf In PDF document text
    • https://taevlingar.se/images/pages/file/bejubavowed.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe815b7a1d---97400066584.pdfIn PDF document text
    • http://nbnjl.com/userfiles/files/xenepu.pdfIn PDF document text
    • http://www.injamal.es/nueva/ckfinder/userfiles/files/waxokep.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b170514976f---popitunokagopelis.pdfIn PDF document text
    • http://wjvanderheidedienstverlening.nl/uploads/file/59257355699.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16076a59fb3818---xezuzeduwipilakijixuzu.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076cf86ba182---xarumogilofinapozoweniben.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/0ca45e1ee8df126b1e4f4c1b82e18421/womipajugejenu.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/c69c10225cff286633193716854a3ece/pobiduxenowif.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac21f614da9---55435059114.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/5d52b7b93c519c38c4d8eaa774535611/zerufovixudorewojo.pdfIn PDF document text
    • https://advance-pack.com/editor_upload/file/xebabu.pdfIn PDF document text
    • https://mimpiindah2.com/contents//files/zubugitavawesezufug.pdfIn PDF document text
    • https://immo-cjeanpaul.lu/userfiles/files/32467468965.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607fbe4101891---xukexaveka.pdfIn PDF document text
    • https://irepairplus.nl/app/webroot/files/userfiles/files/41054534933.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/moxurudonaxutod.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c677a35886---39892377383.pdfIn PDF document text
    • http://nuraski.pl/wsg/userfiles/mojawazuzopupubifexip.pdfIn PDF document text
    • http://tpokebar.com/uploads/files/wofexefeme.pdfIn PDF document text
    • http://ozanatalan.com/iboard/includes/userfiles/files/zebodesupazosufujedizo.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/vo9sktdkc2aj8m4cn6flphvuhs/35729210427.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=scunner+kaiju+toyPDF 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_off0000c22f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC22F 17172 bytes
SHA-256: 0e505fe962bf776ad975942f4f85754c5dfeb2e056857904198718d5be171439
font_01_sfnt_off0000ee9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE9C 10520 bytes
SHA-256: c134f1af393e086502c601d58f27afd90bdb1211a5919de2ad3916e731c34f1a
font_02_sfnt_off000106b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106B7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1