Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9d4dca0042bb253…

MALICIOUS

PDF

89.8 KB Created: 2021-07-12 17:13:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7a10228b609c45982f12d42b5eefb58f SHA-1: 8c7cc6ccd5f32dd9451c3a3726d10cd7fa27d60b SHA-256: f9d4dca0042bb2530be3de30d3d4150da312897de62e827a0d4003b8d31d1776
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised WordPress sites, suggesting it's designed as a link farm for phishing or malware distribution. The ClamAV detection and ML classifier strongly indicate malicious intent, likely exploiting PDF vulnerabilities to redirect users. No scripts were extracted, but the heuristic findings are sufficient to classify this as a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 https://ketchas.ru/uplcv?utm_term=cosecant+of+30+degrees
    • https://ihotel2b.com/upfiles/editor/files/wanux.pdf
    • https://sharadsangam.org/UserFilesTwo/file/masuw.pdf
    • https://aulacvn.com/upload/fck/file/15937739868.pdf
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/dd634500bbb626ff7012591f7e893883/mubizapujulok.pdf
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/2iap9sl3s8uc69m2apjqt52bs6/mukezefeminuzitufejiwu.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b65b82ba421---1350612634.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160dc39d8cf8bb---70600654487.pdf
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160af59ecd0689---68397134468.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad7088b681e---nizamoluledutesu.pdf
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/ed2839c8930ec4c9eafae6bd072786de/jobememi.pdf
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/160e8c889a6977---mopikitemedoninokajogedi.pdf
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/e8972c7919b71b32e0995ac97893f769/46684319642.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b732a2bd5bf---nipizitoxirofi.pdf
    • https://fcr-fomentoconsumoerenda.com/uploads/files/78639852459.pdf
    • https://vildmarksjagt.dk/userfiles/file/33263797689.pdf
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4a1d44942b---98429748609.pdf
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088bc484ac84---zajuzozexonagebaxujojusov.pdf
    • https://luathoanghuy.com/uploads/files/ferifaxup.pdf
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1fd54e3dac7fde17837af2fbacafcf5c/93423934994.pdf
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/5822817950589f0665f2190e0ec02188/79444532557.pdf
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160840b2b8546c---46363701198.pdf
    • http://handlpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/boxopaburejoxusikiw.pdf
    • https://aquafilling.com/userfiles/file/notezixoralizivubom.pdf
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/df6a4765490be303d0ebf70f3259f051/87998954230.pdf
    • 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_off0000fd68.bin
0e5c7a73924cb7d23cc13fe10329ab1d0d0798924a1019d5c876a6c9546142f3
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD68 10840 bytes
font_01_sfnt_off00011669.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11669 16792 bytes
font_02_sfnt_off00012e7b.bin
0bac8f86b96c281f0738e3aaa1e0b56ff95e76687cae195cc6f9da20930eb09c
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E7B 17208 bytes