Malicious PDF — malware analysis report

Static analysis result for SHA-256 e31f6ec29a055c92…

MALICIOUS

PDF

91.6 KB Created: 2021-09-08 00:30:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 43bd2eac91cc4301c4e3e118e9c16995 SHA-1: 6e2ddcb3dcf997ffb7b3d8b3d75af18d5b808ea6 SHA-256: e31f6ec29a055c92fe29cc08a696f273075477cd51b2477aa68ec4c43e0c6861
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of multiple external URIs and link farm heuristics supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://snsi.jp/image/news_file/jorowesoz.pdf In PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16123b8aa08e75.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1612d01c7d085e---solujewajog.pdfIn PDF document text
    • https://almavilag.hu/files/files/68803213313.pdfIn PDF document text
    • https://towa-aaa.jp/userfiles/file/vufatiwi.pdfIn PDF document text
    • https://otartufo.com/ckfinder/tartufofiles/files/57067917134.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/77707323419.pdfIn PDF document text
    • http://techscreening.com/userfiles/files/lomajaveronivuvam.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16091dc267ba38---vukasajedinibibojage.pdfIn PDF document text
    • http://pekingtogo.com/uploads/files/fanufibutopasuxaku.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094a2cfa4587---18169303515.pdfIn PDF document text
    • http://lnshiyue.com/userfiles/file/20210902014612_1479505682.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160b7661fb444c---54449755906.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c144e5d748---49114104934.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2c250ce6b---462690591.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/9f74986bba23b04ffa241f606794f982/21076936480.pdfIn PDF document text
    • http://namlongprojects.com/images/uploads/files/85323798305.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160c5d918e1f07---74657743438.pdfIn PDF document text
    • http://zap-interactive.com/uploads/files/jotuwasekutuki.pdfIn PDF document text
    • https://makenie.com/upload/files/39187008086.pdfIn PDF document text
    • http://erisalaw-chicago.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/39130169527.pdfIn PDF document text
    • http://ansing.nl/userfiles/file/kasekekajemeredoviluz.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/7opa53l34onpqnu6s1h8kplelg/87686816059.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/5f8a2df0ea76fd262649cfe4b75805a7/29882893363.pdfIn PDF document text
    • http://namngonviet.vn/user-/files/94694460002.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=manejo+forestal+sustentable+en+mexico+pdfPDF 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_off0000fb8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000113a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113A0 19812 bytes
SHA-256: c041b3627927d1ce439f7d661834dbfa1ae4f90a36da4ac0259ab4fa9f6989f5
font_02_sfnt_off00014609.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14609 11244 bytes
SHA-256: 984dbfd8f1d44b4d00e7049d0812b043ab9f6a815e89833e309ad29350b4af6c