Malicious PDF — malware analysis report

Static analysis result for SHA-256 37494c8f18b4540d…

MALICIOUS

PDF

101.0 KB Created: 2021-08-15 16:00:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 65666519cf642b62fedc3cf101335456 SHA-1: a7555949b7f577ba4f40b1ed34985f5c72140ae5 SHA-256: 37494c8f18b4540db1bc50119c54e64fc85b0c2a39702a3bfc3a80c0470b076a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links, many pointing to compromised CMS upload directories, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the PDF structure itself is designed to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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 https://majubesar.com/contents//files/xofudoladojebuwa.pdf In PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/0d7e34a51f43890905cb37798221e8b3/pelesufalaxixegoleguxo.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/66845543679.pdfIn PDF document text
    • http://ha-sine.com/d/files/19882950432.pdfIn PDF document text
    • https://freedomhypnosisnyc.com/wp-content/plugins/super-forms/uploads/php/files/285157172e5a4e16a19653167fb93b91/sisetaxazupesebim.pdfIn PDF document text
    • https://www.litesourcenc.com/wp-content/plugins/super-forms/uploads/php/files/d54884cba8a3be3ee0c5a50ab790bd57/besopipivefokoxenevilemu.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/1222a2e8de079f37584bbf8710282c6b/woxirafobozozotewusawi.pdfIn PDF document text
    • http://opusbiz.kr/data/editor/file/116662288260e94ddfecdb5.pdfIn PDF document text
    • https://eberli-medical-supply.ch/upload/file/kixojudes.pdfIn PDF document text
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/hht2d1p3cdcm255fu7qr6nf403/rixipo.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a1ef0b3e321---36590270076.pdfIn PDF document text
    • http://lavalnerina.it/userfiles/file/muvetozoxosibuzoporepemar.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160af9eeb0d28b---satijodomatase.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/160a6e342f2b63---jesuzofunuziginon.pdfIn PDF document text
    • http://www.skk.com.hk/admin/ckfinder/userfiles/files/sagonarupazunikawi.pdfIn PDF document text
    • http://cuatudongbinhduong.net/uploads/files/8625653687.pdfIn PDF document text
    • https://beldaoyun.com/calisma2/files/uploads/87767776924.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ace32b69115---97398792336.pdfIn PDF document text
    • http://ruresept.ru/files/file/34826405789.pdfIn PDF document text
    • https://hkfew.org.hk/ckfinder/userfiles/files/33939858354.pdfIn PDF document text
    • http://bigxra.com/uploadfile/file/2021051517025473499.pdfIn PDF document text
    • http://dakmoto.cz/obrazky/file/5419233644.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160988a0188715---zunow.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/jkqoql805n3k0q0r5a140ht046/7580306818.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/83963bd62dbe1a5f55642d60ff0a78ff/vasivuvodiled.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/fps0m6f4o4gv9521h8ghbtrtm4/38167617806.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=icse+class+6+english+literature+book+pdf+free+downloadPDF 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_off000122ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122EF 11436 bytes
SHA-256: 32f76942989c84a410d2162d77345458daac23f242e1d56cca7b69d37ac4e1c2
font_01_sfnt_off00013d88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D88 18108 bytes
SHA-256: 730704ae96034e7df5e4353adbb6b93fcaeeced018101225d2197159d5e692d7
font_02_sfnt_off00016d02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16D02 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1