Malicious PDF — malware analysis report

Static analysis result for SHA-256 d12e3edd5e460d9d…

MALICIOUS

PDF

75.2 KB Created: 2021-08-17 09:05:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b1847fd429f6a7013058f011fe04f878 SHA-1: 77e535c108b66d3031f7e03c374f4de1d0d42524 SHA-256: d12e3edd5e460d9d25c6be799c66aa313a7a27ef6bce1d82da44b59f50fb17c9
156 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs pointing to compromised websites and potentially malicious PDFs. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a non-clustered link farm on disposable hosting, and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' highlights links to compromised WordPress upload storage. These elements suggest the PDF is designed to lure users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://datong-travel.tw/upload/ckeditor/files/20210731221842.pdf
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a629e707a96---wowutedebupotaxofal.pdf
    • http://primehorseproperty.com/userfiles/files/98154758969.pdf
    • http://webcertain.asia/contentupload/fckeditorUploads/organization_/file/64397883937.pdf
    • https://pacpartner.net/images_client//imagesfile/26808008216.pdf
    • http://mtecommerce.it/public/news/file/58637240508.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d1cfc5ea9f1---63871015985.pdf
    • https://oumkua.com/userfiles/file/gobetufevexaj.pdf
    • http://deeringbayrealestate.com/userfiles/files/fotuvezabotugok.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ad05baf24d---nivemazuzebakaguxowenovu.pdf
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608294af187fc---xajizesafu.pdf
    • http://studiotecnicobonoli.com/userfiles/files/54974895826.pdf
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085d65a60232---21012886369.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16072ad5b4dcba---76549497062.pdf
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf5205437e---46592860109.pdf
    • http://ohmytour.kr/FileData/ckfinder/files/20210630_30505FBEC944F7E4.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607affee42ba5---48762224285.pdf
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb261afa19---69960821392.pdf
    • https://trade.inter-ural.ru/ckfinder/userfiles/files/70978052420.pdf
    • http://rauvuonsach.net/images/uploads/files/tasiwesewu.pdf
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607fbd7d315bb---ratugilorowuwovurawujov.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=exercice+g%C3%A9om%C3%A9trie+6%C3%A8me+droite+segment+demi+droite
    • 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_off0000c146.bin
dcd91d91cf8581476269010ec94bb3423279da1d84b791b428c151870f32566f
pdf-font-stream PDF embedded font (sfnt) at offset 0xC146 11068 bytes
font_01_sfnt_off0000da32.bin
fb71bd678dd35de801abb1a042155f6c60a8c730d742b1b6a15ee439b261bb2e
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA32 16432 bytes
font_02_sfnt_off0001040e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1040E 16792 bytes