Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f8a83ef56677522…

MALICIOUS

PDF

76.9 KB Created: 2021-07-27 10:17:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3236e07fdc94dcb206df61d6e6b5bdab SHA-1: b43f5e8272a2184b03132570de48a08d85e31795 SHA-256: 4f8a83ef56677522bd30191ba46413e474b87280a9773813a13d83f82fdb8e2c
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs that point to compromised WordPress sites, many of which host other PDF files. This behavior is indicative of a link farm designed to distribute malicious content or lead users to phishing sites. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/54e00b1bc2cb010ef4c2aca879bca9dc/81446328872.pdf In PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/16085bfa7d8e2a---2634070807.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/0405b5cf6455187ab787c94fca19bfd3/25683507048.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/d8b12c75ec9b77a281094212e20cc2a9/tinixinavaw.pdfIn PDF document text
    • http://wolfpackbasketballacademy.com/content_docs/42205116520.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/955a8180cd11826219adeea58b9a3efd/65156280763.pdfIn PDF document text
    • http://www.bash.cl/media/file/vajofavorudeviwexabiv.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16079d7bdee4d5---vaxepakusetigilixeta.pdfIn PDF document text
    • https://www.aserspa.net/wp-content/plugins/super-forms/uploads/php/files/aeqvt79n44fikquq5i4ad71pnd/97740035144.pdfIn PDF document text
    • https://cualuoihoanmy.com/uploads/userfiles/file/pobara.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/nudide.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/16075a12ce696a---7013037676.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c0d27d7aa7e---jusasedogikow.pdfIn PDF document text
    • http://cheapmarkt.com/userfiles/file/miwodelipum.pdfIn PDF document text
    • http://samuiluxurytravel.com/Uploads/file/kiguxeb.pdfIn PDF document text
    • http://robbinsfamilyhealthcare.com/clients/2/2c/2c787fa606fc56c3a3a24dfc5409695f/File/80598664755.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/pupiliwero.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/cq4qto228a6quh48ska1j42214/gusexamenubiruwuwux.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160889d04ae15c---80666162000.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=tzumi+wireless+charging+alarm+clock+instructionsPDF link annotation
    • https://www.thc.gda.pl/ckfinder/userfiles/files/todokezokizawonilutugusoj.pdfIn PDF document text
    • 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_off0000c6f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6F1 10980 bytes
SHA-256: 0f06979834b24386eef43ad6e67a6a6ca551c1162552da093440e80b1ad0fc93
font_01_sfnt_off0000e05c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE05C 16536 bytes
SHA-256: 23cd6f1d433c3930d374aaecc3b5f027ea2dde1f95c1f71ab86099e6c6a710bd
font_02_sfnt_off00010b1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B1E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1