Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c0cbc825615aa0c…

MALICIOUS

PDF

83.7 KB Created: 2021-09-06 20:22:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ecd5252d6d192eb8a42d2e477e97971e SHA-1: 19d1d91a6fcc7a95e4b03e1910b3bf39479c5a21 SHA-256: 5c0cbc825615aa0ccdbb59d86528383d3bbfc53f8a2484a296c3fae269750d12
156 Risk Score

Malware Insights

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

The PDF document contains a link farm pointing to numerous other PDFs hosted on compromised WordPress sites. This behavior is indicative of a phishing or malware distribution campaign, where the initial PDF serves as a lure to redirect users to malicious content. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/dbdf77d9027099951c50d05e701bb8fb/44012331072.pdf In PDF document text
    • http://hb1004.com/userData/board/file/83240632177.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-5-16/20210516152550592542.pdfIn PDF document text
    • http://shesob.com/file/files/44295939772.pdfIn PDF document text
    • http://xn--h49al33a2zdp0eo1x.com/DATA/file/20210903061149.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/371fa067417aac3f863c08aa9d3e6cd1/ravadoluvarosakufuwid.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160cc6ce63451e---karijil.pdfIn PDF document text
    • http://coreaad.com/DreamDataUpload/file/givukeruj.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/7e417d83bb550b296ce261375b415c70/98563090260.pdfIn PDF document text
    • http://carrozzeriardue.it/userfiles/files/7171918183.pdfIn PDF document text
    • http://gld-lining.com/user_img/files/69123232403.pdfIn PDF document text
    • https://cbconsulting112.ca/userfiles/files/wusenebebasozikinurutubav.pdfIn PDF document text
    • http://dannguyetltd.com/upload/files/wowobaselozagomozorupa.pdfIn PDF document text
    • https://vendax.ro/files/file/92141064993.pdfIn PDF document text
    • http://planbmedia.hu/files/bibatuvapez.pdfIn PDF document text
    • http://truthtube.com/UserFiles/file/vagub.pdfIn PDF document text
    • http://handbook.hu/upload/page/file/zadiwe.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1611158dd4327c---mufesabaguvefam.pdfIn PDF document text
    • https://aterhesseg.com/up_image/file/62187546752.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/9c4f33d63da06f9186e487966e4d611a/49615637668.pdfIn PDF document text
    • http://tzoetemondje.be/uploads/files/82200454129.pdfIn PDF document text
    • http://orhs89reunion.com/clients/77823/File/83757611177.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=rail+europe+experience+map+pdfPDF 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_off0000e365.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE365 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB7C 10760 bytes
SHA-256: 5e88680cefa0cda95a13e051570ec0654c5488f65f583324be359a9966369448
font_02_sfnt_off00011423.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11423 17332 bytes
SHA-256: 9494b1d02c968758de5ae4c917a361671d83e255f203ca8b470c117b6aa757ae