Malicious PDF — malware analysis report

Static analysis result for SHA-256 21225a2915a2c642…

MALICIOUS

PDF

83.3 KB Created: 2021-06-29 00:04:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e173737d8a8e2ffbbccaa9f337ec98cc SHA-1: d28eb9a041f415237b0199012b55face6211efb9 SHA-256: 21225a2915a2c642693072370b58b93f88d05bfa8e3e429061a2efece191709e
156 Risk Score

Malware Insights

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

The PDF document contains numerous links to external websites, many of which appear to be hosted on compromised WordPress installations. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or to serve further malware. The document body is heavily obfuscated and does not provide direct user-facing content, suggesting its primary purpose is to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9946

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://krisoc.ru/uplcv?utm_term=solange+knowles+smith
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/e28989902ecb9a724310570177be5e6e/792834265.pdf
    • http://dominoliberec.eu/images/file/files/xutezonupipoxa.pdf
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/495e48b6ae2c79c1eab9e1e4f75147b0/56721343916.pdf
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/b0fffad519ad68073be62163b023ec97/7147021255.pdf
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160a4d058531b8---84323352570.pdf
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160928ee625bcd---fakipekatularosa.pdf
    • http://banglatalkies.com/dynamic-images/cms/file/15360410992.pdf
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a5e586454c---13991113288.pdf
    • http://globalsocialwlefaresummit.com//app/webroot/uploads/ckuploads/files/93505927142.pdf
    • https://www.citysecurity.org.uk/wp-content/plugins/super-forms/uploads/php/files/t9asai5i42ghnu71to9tkgdovp/bowewifowumofaxurokagow.pdf
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/6cb76ef5a82762b4b6250e2b6ab80d0e/menamerufebef.pdf
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/1b858206acd467661b5b5b31f8c9a351/62269210234.pdf
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/39f9beb4a633cbb88be5aa7def0223dd/kesokigelefisozep.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/6af6dcf74366afb91a9e56b6e2c57e11/69462547809.pdf
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/373440f8ccfbf9845988e46e1b92eceb/66510674862.pdf
    • https://e-lightingcontrols.com/wp-content/plugins/super-forms/uploads/php/files/8200dbccfd2efb49f5df187725ec7a23/jugilixitadim.pdf
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/48e8dfed80ddc3325a18f6f629cbb72f/nunazoj.pdf
    • https://bonacorsi.it/file/kosonajekojigobafesu.pdf
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609d9f2d0feb9---dikija.pdf
    • https://liniagdanskzydowo.pl/files/sufutowigawireleg.pdf
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082b1aa4584f---wewogemoxodelesasofavu.pdf
    • http://nordicaluminium.ru/userfiles/file/26349954461.pdf
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/bns4c5qbqn2sunsk8241ptc7v2/midodanopakigod.pdf
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d27006513a---72433369093.pdf
    • http://boxethai38.comupload/file/rafavekususawatav.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_off0000e218.bin
905af1337f4d5a6e9932fc56c42345305402aaea7aaeb5b28f2fbd75a6c026f3
pdf-font-stream PDF embedded font (sfnt) at offset 0xE218 10708 bytes
font_01_sfnt_off0000fa87.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA87 16792 bytes
font_02_sfnt_off00011299.bin
610839646790ca83367eaa29b0744d6ef6356cfa94128b4e4f002b894fd3c74a
pdf-font-stream PDF embedded font (sfnt) at offset 0x11299 17116 bytes