Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d51cb3eb55cfd3c…

MALICIOUS

PDF

85.4 KB Created: 2021-07-18 00:12:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 1823813b340cb14abe8459bee884e997 SHA-1: 2e36c5f72c646e3563a979f21a9462ed70176260 SHA-256: 3d51cb3eb55cfd3cdef5fc4096d5fad38dd7f77898066912c72355ad7279c3f7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • 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://m-co.de/wp-content/plugins/super-forms/uploads/php/files/49pqj9sore1etraosvvokhjeu2/nenojawitomikaxorul.pdf In PDF document text
    • http://bright-inter.com/file_media/file_image/file/23532687934.pdfIn PDF document text
    • https://inncredel.com/uploads/zexujor.pdfIn PDF document text
    • http://lowry-averyreunion.com/clients/c/c0/c0e4e7922159a76f956c19110b7bfeb7/File/93828508850.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608784d0c6441---divese.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b05887ae1a---93385223167.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607197b818a26---88805258641.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b4c32d97c00---fufebetivusujak.pdfIn PDF document text
    • http://geologocarmignani.com/userfiles/files/45479381757.pdfIn PDF document text
    • https://bikidi.com/UpFiles/WebEditorFiles/file/33623080545.pdfIn PDF document text
    • http://barrybusiness-crm.com/ressource/devis-photo/files/973757938.pdfIn PDF document text
    • http://safeabortionnepal.com/userfiles/file/1737779366.pdfIn PDF document text
    • http://amandatour.ru/js/ckfinder/userfiles/files/10404582603.pdfIn PDF document text
    • https://rcot.org/userfiles/file/xomoxoxexo.pdfIn PDF document text
    • http://agisma.ru/files/pages/files/43043841322.pdfIn PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084eb356e78d---40684604381.pdfIn PDF document text
    • https://laser123.com/geektic/files/94338120113.pdfIn PDF document text
    • http://eva.am/files/4de7e3eba6d0e76a.pdfIn PDF document text
    • http://artdealer.vn/upload/fckimagesfile/2d0ae282434c5b135676989cc658b1cf.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/355fbecea81933678b21898a7db38363/7685445628.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/314b6e53cc8eb3f7037d9d8d7337679f/pibijewepavitebaja.pdfIn PDF document text
    • http://raykingcarroll66.com/clients/2/29/292092747e06e0ab09130fa737b110c0/File/18549190453.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/iajln4arltbnh9pjphcqicm2sv/zasugakawodanudanulobi.pdfIn PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160728c82f0b88---50385113177.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=claude+monet+the+woman+with+a+parasolPDF 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_off0000e92c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE92C 17776 bytes
SHA-256: 98c9e10e7f7ecceccee31a8a3c636836941bbd3db157ccc66d1d7785c799bda8
font_01_sfnt_off0001173c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1173C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012f53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F53 10876 bytes
SHA-256: d6967bb6690fef22cb3b02c2e7d4146b009ade8557c40ea1337a8df80d3c13d3