Malicious PDF — malware analysis report

Static analysis result for SHA-256 c16146380a57c701…

MALICIOUS

PDF

91.8 KB Created: 2021-07-10 13:28:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2f574215234952b5c53bb0d525cef2cb SHA-1: b6b8574ec96aea88f1541f6261be81e808fa6b4a SHA-256: c16146380a57c7017e99fb5e640fcc39cd97c3aa9f6a452e3f2dc7a79876e79d
96 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, supporting the assessment that it is used for malicious redirection. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/160bad45c0e59a---62082822719.pdf
    • https://pt2-turbo-j3t.com/contents//files/papexokub.pdf
    • http://beiks.info/public/file/2989814329.pdf
    • http://alphabodysupplements.com/newerac2c/userfiles/file/suxak.pdf
    • https://mimpiindah2.com/contents//files/72751504433.pdf
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160a26a20883d0---ludewapiruritepe.pdf
    • http://bookblog.kr/data/file//files/3781633377.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/2qfta2mj19gprglnuhbfitqoqn/86792095633.pdf
    • https://muzeumkonstancina.pl/attachments/file/65444405604.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/63bfe3520752e927a5fd2cadf4badc46/94686591000.pdf
    • http://portalinmobiliario24.com/uploades/fckeditorfile/42117906236.pdf
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/o7kukh9p6s40l1emgipv19k02m/gegilonewitumobukomixuv.pdf
    • http://sistarelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wipesuwerivesonuwat.pdf
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608d47786d949---gunakowusuwedoju.pdf
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074884ba90da---16099403000.pdf
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/9930d4e15d4ef53cb4c27d1e3db00d8c/96807146395.pdf
    • http://seanmore.com/userData/board/file/livas.pdf
    • http://teechart.com/uploads/images/files/58401166447.pdf
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/f4285c0ec518c78943463769cf5c2041/6245630988.pdf
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607e914184e9a---dukagagexizivunidumav.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=how+do+you+ask+a+question
    • 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_off000106c1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x106C1 16792 bytes
font_01_sfnt_off00011ed3.bin
0defe94735c5582532d89cfc651c9f9b12f4f36c59e9deb26e999c1430160300
pdf-font-stream PDF embedded font (sfnt) at offset 0x11ED3 16576 bytes
font_02_sfnt_off000149e1.bin
6d37bf30f551936d2fd19479041bc570b475cd0d2b51a1961d0db46d57525bac
pdf-font-stream PDF embedded font (sfnt) at offset 0x149E1 10624 bytes