Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4a4cbdc521b62f4…

MALICIOUS

PDF

80.7 KB Created: 2021-08-23 17:07:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 99d0b21f84370ed11ab7b6346e20b781 SHA-1: 740e198098f96317280b93e215dce432489727a4 SHA-256: c4a4cbdc521b62f4506376f1e71940517a4d15f5da1d1ca99b480880e75ea8f6
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of numerous links on disposable hosting and compromised CMS uploads reinforces the phishing and distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b96d0f824e0---75741573696.pdf In PDF document text
    • http://buyyoutubecomments.com/ci/userfiles/files/xaxugubixizulaju.pdfIn PDF document text
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/u5knsf08fakmqooolgdb2n1kj3/ruletute.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e0a3af8b3---munokokanozegevedimoz.pdfIn PDF document text
    • https://imotrading.com/images/userfiles/828502016.pdfIn PDF document text
    • http://classtool.info/upload/files/7445515764.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/2284a5479207bbe86615aea435e4b422/xaxijuzowo.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b0697732b3f---xawaxiseweputikexob.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/160904c817b084---rimax.pdfIn PDF document text
    • http://bakoca.hu/files/file/71899559901.pdfIn PDF document text
    • http://toyteepee.com/uploadfiles/file/210615135145822977t34tz1.pdfIn PDF document text
    • https://hotelindigha.com/FCKeditor/file/64622510243.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16088a1df9d718---natufexitavejo.pdfIn PDF document text
    • http://fijiembajak.com/uploads/ck_uploads/files/71344867583.pdfIn PDF document text
    • https://lamaisonducoeur.ca/upload/editor/file/14120149564.pdfIn PDF document text
    • https://myarchitect.es/ckfinder/userfiles/files/70877206664.pdfIn PDF document text
    • http://cephedanismani.com/images/pages/file/busopim.pdfIn PDF document text
    • https://crownprolaw.cn/userfiles/Proj_Name//files/sivovexodomudoxibum.pdfIn PDF document text
    • http://mobiliteit.nu/files/lilufujodunobuteguf.pdfIn PDF document text
    • http://misterholidaysanprisco.it/userfiles/files/lavologureruzokeg.pdfIn PDF document text
    • http://capitolmetrophysicaltherapy.com/files/files/kedisisigaze.pdfIn PDF document text
    • http://tauben-buchmeier.de/kleinberliner-schuetzen/userfiles/files/rewarudagusoxuwad.pdfIn PDF document text
    • https://adtw1.com/ckfinder/userfiles/files/kikokekuga.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/42lql78oiifemvch9b1reofjl5/90858763881.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/16098c55373bbd---zebanoganurarunufow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=gta+v5+apk+download+for+android+and+iosPDF 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_off0000d7dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7DC 10776 bytes
SHA-256: 337ac5f30d2e7a4cd54d8b0b2f505a601fb9d16fddb39ecd00859f0b17072397
font_01_sfnt_off0000f0e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E5 16500 bytes
SHA-256: 82881d95016e1186295b3955c653330a38701025f3a28bdf19b180eac9e51848
font_02_sfnt_off00011bf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BF9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1