Malicious PDF — malware analysis report

Static analysis result for SHA-256 13b17f8a510e3605…

MALICIOUS

PDF

81.4 KB Created: 2021-09-16 18:43:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: def71804a094b85a7ae6f0a5d6d3449b SHA-1: 841b7413d23a883b715c734fa98ab065a40f07ad SHA-256: 13b17f8a510e36050245b3a626c0412f7e6f92990698e0d79d1ef4efd2774ade
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, indicating a potential for malicious execution. It also features a link farm pointing to multiple external URLs, some hosted on compromised CMS uploads, suggesting an attempt to redirect users to malicious or deceptive content. The ML classifier strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://akanaymatbaa.com/calisma2/files/uploads/73643821446.pdf
    • http://ventmetal.ru/userfiles/files/bopopatorujevezoxus.pdf
    • http://bctlorraine.org/userfiles/file/45968992238.pdf
    • http://mxag.com/upload/browse/file/wedamego.pdf
    • http://kruengrangthai.com/files/files/41185673064.pdf
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd242eece3---24560218268.pdf
    • http://www.julietlandau.com/fckeditor/userfiles/file/fivizur.pdf
    • http://architettoseneca.com/userfiles/files/xosiwazaxabalune.pdf
    • http://xahscw.com/userfiles/file/51555466697.pdf
    • http://e-park.es/img/uploads/files/lazewutupa.pdf
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/2942d8d89319e55fceee552a3eb51185/kobomajutifunakojekajokum.pdf
    • http://squarcialupirelaxinchianti.com/writable/public/userfiles/file/75030507076.pdf
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1613bbed2295ff---28876152870.pdf
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161328f5828edc---lerisejitesexeg.pdf
    • http://khiensa.com/UserFiles/File/zegamovakurufakenarafata.pdf
    • http://zonazero.es/userfiles/file/xuvakumakubejosuda.pdf
    • http://www.teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/64447255112.pdf
    • https://myagenda.myagenda.cz/pictures/editor/files/xipawamuju.pdf
    • http://ghibms.com/userfiles/files/likurux.pdf
    • http://mpwlawpa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jabunitijizufixepaxuzozi.pdf
    • https://silatur.com/js/ckfinder/userfiles/files/pegemopefuk.pdf
    • http://classtool.info/upload/files/95715178798.pdf
    • http://ketoanantamhcm.com/uploads/files/56342491518.pdf
    • http://lingvastar.z-i-g-z-a-g.com/userfiles/files/lanunogo.pdf
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/b2713d12a2ad30820aa85673359be776/97241017277.pdf
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/t452stkhqpntgdebfkahka77r1/54303952322.pdf
    • http://syuncyoku.jp/upload/file/14728389229.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=toefl+listening+pdf+with+audio
    • 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_off0000d82c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD82C 16792 bytes
font_01_sfnt_off0000f03e.bin
374afd15673f5f2f5f67afd14d1252dd9a391488f3aa16a576a0a0c0bad9f129
pdf-font-stream PDF embedded font (sfnt) at offset 0xF03E 18188 bytes
font_02_sfnt_off00011f5d.bin
44f34e76af28e3c263141b4e101dd154be3bbccc1e630a0c6a7e80a5ffa9adbf
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F5D 10828 bytes