Malicious PDF — malware analysis report

Static analysis result for SHA-256 753b194fab53cdde…

MALICIOUS

PDF

67.9 KB Created: 2021-09-25 11:08:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 98c29c92441bdf476cf9b826d6dd3e7b SHA-1: 1de213d8ba3937e1a0c579c43ab24d2f8770c085 SHA-256: 753b194fab53cdde66c3259aa10151bf89fec40ccd387acebc1788fb823fbf96
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. It also features a link farm pointing to multiple potentially compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • 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://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/22ae862cf39b4789d41ccf5ddd221cbe/6437582774.pdf In PDF document text
    • http://hndgyl.com/v15/Upload/file/2021911124406276.pdfIn PDF document text
    • http://franchisefarm.franchiseharbor.com/files/files/98486837919.pdfIn PDF document text
    • http://sochi-polyana.com/ckfinder/userfiles/files/xutabomomidibalino.pdfIn PDF document text
    • http://faradbox.pl/files/file/wumosix.pdfIn PDF document text
    • https://mokhalasati.com/userfiles/files/xitapaze.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/jupukosalovakoruja.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614710a9642f3---72862565044.pdfIn PDF document text
    • https://krusomying.com/data/file/rejixinebebuxufo.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613634c3d28ed---benami.pdfIn PDF document text
    • https://tvmreza.tv/ckfinder/userfiles/files/lemekifepadut.pdfIn PDF document text
    • http://pazzo.jp/js/upload/files/mejuwefitudizigul.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/161401e3647404---wixorepatumej.pdfIn PDF document text
    • http://ruizhishengwu.com/uploadfiles/file/181600437187.pdfIn PDF document text
    • http://ck-kutnahora.cz/gais/image/file/76405043260.pdfIn PDF document text
    • http://aedelsur.com/contenido/files/tezesedibufimuwuja.pdfIn PDF document text
    • http://st-ark.it/userfiles/files/pojakirevonujiva.pdfIn PDF document text
    • https://behbehaniprojects.com/uploads/files/27323400436.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/16ec6e12adc5122312f54453c8fc6ab8/jijepokaxopiku.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/161389ef104c4d---wosotejofuduti.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=online+games+paper+io+2PDF 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_off0000aa57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAA57 14984 bytes
SHA-256: 8d6e952358722a0de074555f72dad073a77636b1144818ac6c85e8533fe1bcaa
font_01_sfnt_off0000d058.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD058 10640 bytes
SHA-256: c7be6e43af40975f80110d329efbe7c8c9d3739cc176fbb3bd7c901847a59d90
font_02_sfnt_off0000e8b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1