Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b451b72072dbd3b…

MALICIOUS

PDF

80.3 KB Created: 2021-09-21 14:57:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: a1610be18a26179bed10a8609db78f02 SHA-1: e067429f590ee991e0dc170ffcd8f7662f98d244 SHA-256: 5b451b72072dbd3bfbc5ee154e37470457237624fb047dfffc5bc798626d3dab
126 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 distinct hosts and appear to be part of a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The file's structure and the presence of many external links suggest it's intended to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://pjteam.hu/uploads/jinelajiwikuzepokubirin.pdf In PDF document text
    • http://poltinka.ru/userfiles/file/61395399142.pdfIn PDF document text
    • http://nova-auto.com/upload/jubagazis.pdfIn PDF document text
    • https://gogreenonline.net/userfiles/image/fckeditor/file/88880869203.pdfIn PDF document text
    • https://somogyplusz.hu/files/senebut.pdfIn PDF document text
    • http://congseng.com/uploadfile/files/83690992087.pdfIn PDF document text
    • https://weilmclainboiler.ca/fck_upload/file/sipeweluvegukubol.pdfIn PDF document text
    • https://tfsroanoke.com/home/tfs/public_html/new/ckfinder/userfiles/files/gujeputokojejavek.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613f33c2771ea---79405716172.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16146c5548db0d---lojidutejazeforepinuj.pdfIn PDF document text
    • http://nbc.ua/design/pic/file/nosivetirewomegasogujog.pdfIn PDF document text
    • http://samafb.org/uploadfilefiles/36577422258.pdfIn PDF document text
    • http://101-games.ru/images/uploads/files/fefidabiz.pdfIn PDF document text
    • http://lafenicealcamo.it/userfiles/files/mesusosixixaf.pdfIn PDF document text
    • https://www.hinkler.com.au/application/third_party/ckfinder/userfiles/files/fovurifidimunidomeguned.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/welijujizog.pdfIn PDF document text
    • http://marinda.ru/pics/images/file/dadobijulekavoxemojem.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/kopuwum.pdfIn PDF document text
    • http://manu-transport.com/documents/file/kusemutip.pdfIn PDF document text
    • https://cliniquemyo.com/userfiles/file/59270102456.pdfIn PDF document text
    • http://chrislahoda.ca/userfiles/file/ribozilepapig.pdfIn PDF document text
    • http://indianspringhomes.net/userfiles/files/29741658861.pdfIn PDF document text
    • http://epmresearch.org/userfiles/files/90928128031.pdfIn PDF document text
    • http://keystoparadise.com/userfiles/files/wadomevoju.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/50408337867.pdfIn PDF document text
    • http://gibkrakow.pl/uploads/files/wanadejijitanad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=nonton+kimetsu+no+yaiba+mugen+train+full+movie+onlinePDF 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_off0000d331.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD331 17676 bytes
SHA-256: edcfe1dfc2b6d68ad5633ad489bc1c1566058930f65a4f6d80d8915dd5bf9cbf
font_01_sfnt_off000100dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100DC 11048 bytes
SHA-256: e98c7dfb0d17ac8acf28c4fe618a08f5afa93bcc166efea7d499c459733d251e
font_02_sfnt_off00011ab0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1