Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bd251ff33c03e91…

MALICIOUS

PDF

74.3 KB Created: 2021-09-05 00:12:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ed35c2a784fcf03508bfe42d49f252e6 SHA-1: 0d8cb8d45220550fb40c9dc46f172fe43e824764 SHA-256: 8bd251ff33c03e9146aee3d1b7230e04d7b980279d197f5d2a77812ee8772f29
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS uploads or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a malicious document designed to exploit user trust.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://besteva.com/upload/files/wifokodugowekuvuvuwap.pdf In PDF document text
    • https://cecprint.com/images/file/12886982595.pdfIn PDF document text
    • http://synagoge-stommeln.de/ckfinder/userfiles/files/nipozofudanegegevone.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f7b3094d57---75891653261.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1609b444b066a4---lidoxubodesaxolazolivowok.pdfIn PDF document text
    • http://baliretreatcenter.com/olabali_ci/media/images/newsfiles/8712117309.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/4f073f652371aaf41831528368c40824/34257903433.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160baec65afbc8---65135923088.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/6cce886603f7bbf504423765cd42a0c8/9800097872.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/milagujesaweluvulaw.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/nipojokugo.pdfIn PDF document text
    • http://baocaosudanang24h.com/uploads/image/files/90499299985.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210501120007_523221988.pdfIn PDF document text
    • http://wirheiraten.de/images/file/25529642189.pdfIn PDF document text
    • http://daegyung.kr/userfiles/file/20210817055018.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160c8c8c41c589---41395208337.pdfIn PDF document text
    • http://agro-vostok.ru/userfiles/file/37764492989.pdfIn PDF document text
    • http://dui-antidote.net/images/userfiles/file/34359467449.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b1bba0a8042---mujizupav.pdfIn PDF document text
    • http://pogservice.ru/userfiles/file/68201688792.pdfIn PDF document text
    • http://homesunshinepharma.com/upload/files/likijufudimisudubu.pdfIn PDF document text
    • http://zeguvietnam.com/uploads/ckfinder/files/nalegu.pdfIn PDF document text
    • http://gesundezellen.de/neu/userfiles/file/nawugana.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=pronouns+worksheet+pdf+grade+5PDF 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_off0000be4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE4D 16804 bytes
SHA-256: a58f053d853eeeb9d85e013d11ac7f33cc9f1f864e0f9814b7403d4216d8ab46
font_01_sfnt_off0000e9ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9AC 11052 bytes
SHA-256: 26c7cee4f74ab321236ad6d013b3853fe87a470ee6b78e61d522500b03207897
font_02_sfnt_off00010353.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10353 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1