Malicious PDF — malware analysis report

Static analysis result for SHA-256 2880c47889fa2fdf…

MALICIOUS

PDF

87.7 KB Created: 2021-08-21 02:43:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d4e5617598bdfa296ebf670b33b8a506 SHA-1: 062f5b7d93e758d69cb1ebae6feb395fa5900120 SHA-256: 2880c47889fa2fdfcffa5b039b8499c0bd8b945a8c244c3ebc4cd08eb2835eb9
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 and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The presence of numerous links pointing to compromised CMS uploads and disposable hosting suggests a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not meant for direct user consumption but rather as a container for these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://kahounova.cz/userfiles/file/30125482434.pdf In PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b81f2f27a2a---tidijuvumilapewabix.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160810030e303c---16804667031.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/833effac36ff2f7d5b12fce30f8ca134/gonitirimebu.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/sazogupuruwixukuki.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/4286ac597006549272cbdc12a398f328/tabitavufodakope.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c16fd3c8d88---51875643399.pdfIn PDF document text
    • http://accronline.com/userfiles/file/98313402316.pdfIn PDF document text
    • http://lifeisartfoundation.org/sites/default/files/images/userfiles/file/vovakifaxaduxelisaxanet.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/160beec8e6cf6d---95583481369.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/9052866424.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1610b25106b545---korezepapavifiwopiri.pdfIn PDF document text
    • https://pypconsultores.mx/userfiles/file/48054406111.pdfIn PDF document text
    • http://sochisushi.nl/survey/userfiles/files/pofema.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aa7eb870b4e---23948850703.pdfIn PDF document text
    • https://noblacklist.pro/web/img/podborky/files/luxad.pdfIn PDF document text
    • http://splogservice.ru/content/file/gixedevu.pdfIn PDF document text
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a202e186802---dabuwupimizinimovipobegif.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/d7a6a94676296337568827a6550d534c/11681848981.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/bo48p86bc10e3buct5v5roprov/68212100361.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160bbe40ad61ac---vozolabuzizuputorato.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/2bfeedd82e06205c912b83627cc00344/wajupidivijunibetijaxipi.pdfIn PDF document text
    • http://deryalvincotokurtarma.com/userfiles/file/lepofodogeg.pdfIn PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021062303145473499.pdfIn PDF document text
    • http://pogservice.ru/userfiles/file/mogotepuzimaxemujet.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=what+does+the+code+ul+mean+on+a+maytag+washerPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f025.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF025 11016 bytes
SHA-256: db10ec234def8aa08e9656d3aabf6c6d5b9141412d5025815ec8e5f45322ed53
font_01_sfnt_off00010979.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10979 17308 bytes
SHA-256: 17be699b8de37ae6a1af78fe7e819cf1dd81a16d9c2dc0afc37bb6340b7d2ec5
font_02_sfnt_off000136de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136DE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1