Malicious PDF — malware analysis report

Static analysis result for SHA-256 b51118917498b942…

MALICIOUS

PDF

68.9 KB Created: 2021-09-26 15:35:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 327fb14ed8ffb52ec1db5246367877fd SHA-1: 350bf238d66a21ee2adab90ee130c18014bcba31 SHA-256: b51118917498b942b6deb22286aa60410e73c42b0a31c5c735b51f95b337232c
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The presence of these link farms suggests an attempt to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f91b80ab08---gakanetujubaso.pdf In PDF document text
    • http://yeosingol.com/FileData/ckfinder/files/20210919_5914CE6039492BC7.pdfIn PDF document text
    • http://mwbright.com/upload_fck/file/2021-9-10/20210910004636948186.pdfIn PDF document text
    • http://www.la-rocca.pl/app/webroot/files/files/benuk.pdfIn PDF document text
    • http://kco.su/userfiles/file/ruvowenumexal.pdfIn PDF document text
    • https://pfollowers.com/ci/userfiles/files/59045543369.pdfIn PDF document text
    • https://preprodpcb.com/userfiles/files/ruxezex.pdfIn PDF document text
    • http://neboskreb-irk.ru/uploads/userfiles/files/24932920366.pdfIn PDF document text
    • http://rasmesafar.net/basefile/basefiles/95657343320.pdfIn PDF document text
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/wigoziturenagibulonudegin.pdfIn PDF document text
    • https://dalnoboy.com/data/filestorage/upload/files/91169355268.pdfIn PDF document text
    • https://serviceelectric.ca/userfiles/file/valisuzi.pdfIn PDF document text
    • https://96662888.com/editor_upload/file/63026050054.pdfIn PDF document text
    • https://swapnauraan.com/ckfinder/userfiles/files/76656314321.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fdf2acbabf---21840962088.pdfIn PDF document text
    • http://urs-certification.com/gais/image/file/36736438785.pdfIn PDF document text
    • https://novahealthclinic.ca/userfiles/file/93707573602.pdfIn PDF document text
    • http://jtravel.clickis.kr/FileData/ckfinder/files/20210918_8B1529155BA731A5.pdfIn PDF document text
    • http://dc-3ed4d7413bdb.prshots.de/uploads/userfiles/1630592177/files/meratidid.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/cd136c235b55c688ee81260d3db6ba63/xowazuvozizirageparaduxad.pdfIn PDF document text
    • http://vit-physio.de/file/16020393967.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd352860be---85868506189.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=q+quiet+place+2+full+moviePDF 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_off0000ad92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD92 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c5a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5A4 15188 bytes
SHA-256: af84800bb838853329856360cc0c66130a455ae6960fa60b8394ab71a4af2bc6
font_02_sfnt_off0000ebcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBCB 10760 bytes
SHA-256: 7203aae0a676dd190622f45ccca3593c29e7a67eba4ecd8ab6f62c8947d1668f