Malicious PDF — malware analysis report

Static analysis result for SHA-256 51dee2bdcbda0454…

MALICIOUS

PDF

81.8 KB Created: 2021-09-05 07:34:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 604b10c105b51d852c9754fa66ad12f0 SHA-1: 80451f86a3afdce43e86d8d1c8608f4343e476c7 SHA-256: 51dee2bdcbda0454ea98dd5dad5917b435e97b8516fd89a81f9f656dd2eaeac8
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF sample contains embedded JavaScript, which is often used to redirect users to malicious websites. Several heuristics indicate that the PDF links to compromised CMS upload storage and disposable hosting, suggesting a phishing or malware distribution scheme. The ClamAV detection and ML classifier further confirm its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://moraure.net/js/ckfinder/userfiles/files/59878035153.pdf In PDF document text
    • https://detskeihriska.eu/ckfinder/userfiles/files/22060553676.pdfIn PDF document text
    • https://millersexpress.com/userfiles/file/42083314294.pdfIn PDF document text
    • http://samsung-service-center.ru/uploads/files/gitowamibadolusepelizun.pdfIn PDF document text
    • https://fiberglasssupplydepot.com/userfiles/files/nagififofojad.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd615bd06b---78443198289.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/b4e31697f5d17e3c0c4900393f6d4b52/24826844225.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/r2h5bukolsnpfdkaat85hul3h4/sixunutitetoguxanedimi.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/bofefagimuzebij.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160aeb4bacbc50---48141003734.pdfIn PDF document text
    • https://empezo.xyz/js/ckfinder/userfiles/files/5920642421.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d187f202ad.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/d84d12a2769bc6ebfe324fe8cfe9f4f6/2272965362.pdfIn PDF document text
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608db9756b827---40047547593.pdfIn PDF document text
    • https://mn-lawfirm.com/box/userfiles/file/xefuruzedudoxusigofede.pdfIn PDF document text
    • http://127.0.0.1/kardelenemlak/upload/files/fabowovafiseku.pdfPDF link annotation
    • https://marljivo.hr/UserFiles/files/81048476464.pdfIn PDF document text
    • https://mvmdigital.gr/files/files/tefanapodemidezesawuf.pdfIn PDF document text
    • http://dambi.pl/userfiles/file/65688749923.pdfIn PDF document text
    • https://abugfreemind.com/userfiles/file/vujagow.pdfIn PDF document text
    • http://webursitet.org/Files/file/32280952331.pdfIn PDF document text
    • https://pbchistoryonline.org/uploads/file/66452500721.pdfIn PDF document text
    • https://stratasphere.online/userfiles/file/79512471396.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16098a18469a85---52028729239.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=pdf+merge+online+gratisPDF 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_off0000da75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA75 17836 bytes
SHA-256: 1828ba37ce8f7367469c302f596f581c4c6395879c593209ce6f939d7aea1743
font_01_sfnt_off000108ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108BA 10700 bytes
SHA-256: 0fc8577e55cb9baa0885d9d2a89f65e969408465a658bb865b670ee47a10df99
font_02_sfnt_off00012108.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12108 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1