Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e78aa7498e99bd4…

MALICIOUS

PDF

86.5 KB Created: 2021-09-19 00:51:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 533cd6d6bc2b2aa475c11c2ba018b876 SHA-1: 7f92347b00e904b5b8855abb9080faf0295aab1c SHA-256: 3e78aa7498e99bd49bfa83d0fd4940fb56a17c440ae32ed509f8dfef7e36bf45
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm designed to obscure the ultimate destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. The presence of multiple compromised CMS upload links suggests a tactic to host malicious files on seemingly legitimate but compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://szamosiszerviz.hu/feltoltott/files/vorogurovexasopap.pdf In PDF document text
    • http://rosabaum.de/web/editor/files/renuravujujarobowunetisaj.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613d9da4847cc---48976083682.pdfIn PDF document text
    • https://www.comperat-89.fr/ckfinder/userfiles/files/76146434124.pdfIn PDF document text
    • http://st-ark.it/userfiles/files/3759524578.pdfIn PDF document text
    • http://emons-verlag.net/testarea/cwsCMSlight/media/files/41868348519.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161435c9f4d86c---79423772071.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/16133713f9eb55---rojumananoxurufudusew.pdfIn PDF document text
    • https://kanat.com/upload/ckfinder/files/siwuma.pdfIn PDF document text
    • https://securitydm.com/slicice/file/69122582492.pdfIn PDF document text
    • http://avvocatoandreabruschi.it/userfiles/files/daror.pdfIn PDF document text
    • http://cjmfgx.morefriendship.com/upload/files/wevurafovaxufaxexajadeg.pdfIn PDF document text
    • https://ce-mi.pl/uploads/userfiles/files/14723447390.pdfIn PDF document text
    • http://suliaox.com/v15/Upload/file/202192124824032.pdfIn PDF document text
    • http://rs-entp.com/upload/file/55355378933.pdfIn PDF document text
    • http://vncdata.net/app/webroot/uploads/files/zuvizuxewezozujuju.pdfIn PDF document text
    • https://wyslijpaczki.pl/app/webroot/files/userfiles/file/93229621294.pdfIn PDF document text
    • http://gps-tw.com/CKEdit/upload/files/73564880023.pdfIn PDF document text
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/wenabitinotodasopokul.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146560ba9813---17321700925.pdfIn PDF document text
    • http://www.casasemio.com.br/ckfinder/userfiles/files/lewexajemurowugerukeg.pdfIn PDF document text
    • https://szpital-sulecin.pl/images/fckfiles/file/sulol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=facebook+chat+enabler+apkPDF 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_off0000e957.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE957 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001016e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1016E 10420 bytes
SHA-256: af835a7f4dd7e3b6d37074d94aab8b53f16a0ea3c4ea7eb3c3d4485f2a71e43f
font_02_sfnt_off000118bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118BF 19424 bytes
SHA-256: 2fa004190b52ef1b8fbbcd16c6f45dfbbe7f4597e404fca0d7d678b6622e2799