Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7f8cd19866bef33…

MALICIOUS

PDF

74.3 KB Created: 2021-09-19 03:55:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8f7ee999c3296b812e83ac6166891129 SHA-1: 0e1c5b068d86990bb03ab416a0dc8133b8360194 SHA-256: b7f8cd19866bef333960f2af4e9aebebd297746256c122535ae36bd838d86b3f
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm with numerous URLs pointing to various domains, some of which are identified as potentially compromised CMS uploads. These elements suggest the PDF is designed to redirect users to malicious sites or download additional payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://archism.ru/uplcv?utm_term=the+rust+programming+language+pdf+2019 PDF link annotation
    • http://ysmenmidwestindia.org/uploads/userfiles/file/file/gezabateli.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614557f1d1898---wudikigenadijuwuwil.pdfIn PDF document text
    • http://bassonconsulting.mc/userfiles/file/rugom.pdfIn PDF document text
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/6mn6o2621lpi8onlaht233nag7/44254375412.pdfIn PDF document text
    • http://ekhoron21.mn/uploads/files/75992089921.pdfIn PDF document text
    • http://delta-serwis.pl/pliki/kanezez.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/161434732cb29a---14205874197.pdfIn PDF document text
    • http://awfiowv.love-mrt.com/upload/files/92643714337.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d15db9b172---96929823739.pdfIn PDF document text
    • http://rudolphi.nu/userfiles/file/tebim.pdfIn PDF document text
    • http://www.sas.edu.mn/ckfinder/userfiles/files/bodazobolus.pdfIn PDF document text
    • http://dobrasekacka.cz/userfiles/file/97858013757.pdfIn PDF document text
    • https://drhuanghair.com/uploads/files/202109030255432334.pdfIn PDF document text
    • http://ledins.lv/cms/file/9055600318.pdfIn PDF document text
    • http://www.velkoobchod-man.eu/ckfinder/userfiles/files/lubodovizabasuw.pdfIn PDF document text
    • http://hyundai-baoloc.com/luutru/files/leduxisolawixe.pdfIn PDF document text
    • https://bankkartya.hu/js/ckfinder/userfiles/files/mujukegidevanugibodigufi.pdfIn PDF document text
    • http://micronforgacsolo.hu/UserFiles/file/gezidu.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/3ca606203cdb640f9297b8cfe47c3f20/jidawuxalovatibugugamer.pdfIn PDF document text
    • https://sinaia-vik.com/admin/fckeditor/editor/filemanager/connectors/php/file/pawoxuf.pdfIn PDF document text
    • http://capesociety.ca/uploads/files/97841013624.pdfIn PDF document text
    • http://tid.vn/upload/files/kizutulelavezolanuboli.pdfIn PDF document text
    • 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_off0000bcbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCBB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d4d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4D2 11468 bytes
SHA-256: feab3ea037442bb557c294a34d5e38d5a596fb0db19ba9909c8b659506338ee1
font_02_sfnt_off0000ef98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF98 16924 bytes
SHA-256: 8464305fbdc622f20821458b279c9bb34b45a88626bed72c87b1a8a7fbc70c69