Malicious PDF — malware analysis report

Static analysis result for SHA-256 cee9bc6d79bc620b…

MALICIOUS

PDF

88.3 KB Created: 2021-09-04 09:52:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5ef0e39dea32057f459ed2013e35aa20 SHA-1: 27454abcbb40c6834173b15f5cf9162f2ccbc8ab SHA-256: cee9bc6d79bc620b6c84c4729dc57c2263ae8f4322638af3a9f262a5085d9702
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other domains, likely intended to manipulate search engine rankings or redirect users to phishing or malware sites. The presence of these links and the nature of the hosting suggest a phishing or SEO spam attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://laborke.ru/uplcv?utm_term=kia+sorento+2011+manual
    • https://polskieplytki.com/wp-content/plugins/super-forms/uploads/php/files/6253a783c38f7a8bff5b8fa9e727b27b/sukedunabat.pdf
    • http://kaupa.cz/userfiles/file/milereworivowogige.pdf
    • http://topas.lt/userfiles/file/wotemikojuxubavuve.pdf
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/76dc994700b9d94a3340e91637b2246b/94334683457.pdf
    • http://angelcabrera.com/FCKfiles/file/87112882657.pdf
    • http://citescolairedeledit.com/include/file/lubuxavulizopes.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160935935c6a60---66003799062.pdf
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/12b4a69928fddc7fe1ddcb9f9035490e/78149893650.pdf
    • http://personnelstrategies.net/userfiles/file/pomowobo.pdf
    • https://regiefranchet.fr/userfiles/files/47161944627.pdf
    • http://andrelandberg.com/userfiles/file/9797870541.pdf
    • https://gym-rectif.fr/ckfinder/userfiles/files/biwuf.pdf
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/16087b776a01ea---38922727694.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a21b1d5a22f---momubukazizibokip.pdf
    • http://studiogallerani.it/userfiles/files/xunerezo.pdf
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084a7daaf287---dinivi.pdf
    • http://zezoalza.com/ckupload/files/zulelobilizuxesubedemuzif.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610547ae06a0a---joliwilalorafokivo.pdf
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/f80c01df9d4183b7b09c01afd84439a7/46035564856.pdf
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160744496c2e4c---38581617162.pdf
    • http://curry-box-deluxe.de/userfiles/file/lopaxagorezugodarakomorus.pdf
    • http://nhadephoanhao.vn/upload/ckupload/files/jelofop.pdf
    • https://primer-spb.ru/files/files/dinepab.pdf
    • http://dichvuhangngay.vn/uploads/image/files/69465548969.pdf
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16100c704c29c3---vufutasoxekajupoxigas.pdf
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609a591b8e4ce---buzazowelarunaj.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_off0000efff.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFFF 16792 bytes
font_01_sfnt_off00010816.bin
a3812045e80ce17517dc1a77eae819c2c64c9173e3da917b788f5f271eb01166
pdf-font-stream PDF embedded font (sfnt) at offset 0x10816 10652 bytes
font_02_sfnt_off0001208f.bin
89af862b2c53af58b41461d689e3ee0096f68b022ba54678f032d2faf9be9100
pdf-font-stream PDF embedded font (sfnt) at offset 0x1208F 20084 bytes