Malicious PDF — malware analysis report

Static analysis result for SHA-256 51a97e1912e1d06c…

MALICIOUS

PDF

83.3 KB Created: 2021-08-15 12:54:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6c6e17e19e34f82983fe15e1d6727f84 SHA-1: 7c9dd0216ce0c2c631f6c3e926905d6f9a8ced9f SHA-256: 51a97e1912e1d06c78107f84d429ec255dccfa51319695163171995840b89d01
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was identified as malicious by ClamAV and an ML classifier. It contains numerous links, many pointing to compromised CMS uploads and disposable hosting, suggesting a link farm for SEO poisoning or phishing. The presence of external URIs and a link farm heuristic indicates a pattern of directing users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://africanhairbraidingsalon.com/userfiles/file/wodufavepadixakunir.pdf In PDF document text
    • https://adikkedua.com/contents//files/65915543169.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7c7093ceee---javufupilizonofutuz.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/4c41cddfcf85c45eaaae7eea53e67cf0/6940291313.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/q0j0o1nn31t1fseofbv2ao6fh2/fiwofefubosujala.pdfIn PDF document text
    • http://wernitznigg.at/files/32040976288.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a059ca74770---xufikulanekumev.pdfIn PDF document text
    • https://regeneracion-capilar.com/wp-content/plugins/super-forms/uploads/php/files/b592fe8d76c58a4c6952a2bdfedc88a2/novezogalerapusakugaxod.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c021b40833b---77181273777.pdfIn PDF document text
    • https://btsmstlucia.com/atomicsteps/upload/userfiles/file/18052374822.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/fiweporukufo.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210624125156_363477135.pdfIn PDF document text
    • https://poldercuptrofee.nl/site/admin/ckfinder/userfilesfiles/10220558907.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dfd7132a43---gisuxibukegej.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/xuroxafifovuxogiloku.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a50b34f38d3---gefufakafugobuselamifeta.pdfIn PDF document text
    • https://etre-cheval.fr/Applications/MAMP/htdocs/etre%20cheval/news_pix/file/wikox.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/16083c2b5c7f4b---polifukujifoko.pdfIn PDF document text
    • http://foodsafebox.com/ckfinder/userfiles/files/foxezuwa.pdfIn PDF document text
    • http://surausa.com/uploads/files/sasuzigo.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b016625bbd2---79094826534.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080a52fb19f9---subosadetojedaxuruvigisap.pdfIn PDF document text
    • http://yakutiaprime.ru/SITE/files/editor/file/megebudujekevaneli.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0d26206edd---wasokakovisimoduwazoko.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5f602d7ebc---14783791901.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=how+long+does+athlete%27s+foot+live+on+surfacesPDF 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_off0000e27d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE27D 16432 bytes
SHA-256: c9f72759c965546b4f2e27f277765769583ee66f6758017782b0c74d0844fb31
font_01_sfnt_off00010cac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CAC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000124c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124C3 11032 bytes
SHA-256: e70e87ea3d489e4250ea6010b8d750d9630ce29b525b202dc33a54c221e23823