Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd7b7781a95af4c8…

MALICIOUS

PDF

81.5 KB Created: 2021-09-23 16:56:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3a8ec4e2e9714c4f8a7bfd350afeb2f1 SHA-1: 53ee763aa3f2b61369acf27629a0b80b004a1595 SHA-256: bd7b7781a95af4c81bfe6def66baf365efbba459224353e81d3f0af349bb95fe
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to potentially compromised websites, suggesting an attempt to redirect users to malicious content or phishing pages. The presence of multiple external URIs and a link farm structure supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202109111000472205.pdf In PDF document text
    • http://niezapominajkowo.eu/userfiles/file/58532627826.pdfIn PDF document text
    • https://mallorcaboom.com/res/wysiwyg/file/sisijulibolesuxiwimogena.pdfIn PDF document text
    • http://www.kroonzuivel.nl/ckfinder/userfiles/files/pekuwusaxokurirasuma.pdfIn PDF document text
    • http://rpsbchamber.org/editorData/file/16956025765.pdfIn PDF document text
    • http://brickform.cz/obrazky/files/pazerevokode.pdfIn PDF document text
    • http://studioesflores.pl/obrazy/file/36664349360.pdfIn PDF document text
    • https://cubic.is/userfiles/file/kutig.pdfIn PDF document text
    • http://rovitek.com/userfiles/file/62983306564.pdfIn PDF document text
    • http://eska-lift.ru/userfiles/file/37699175269.pdfIn PDF document text
    • https://congnghiepxd204.vn/upload/files/zakalajajoninafeb.pdfIn PDF document text
    • http://www.pacautomarketing.com/file/616962225.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614c4a6da3e1a---57884295869.pdfIn PDF document text
    • http://cokhiminhhien.com/media/ftp/file/39283018480.pdfIn PDF document text
    • http://goldenstarhotel.vn/images/uploads/files/35715792642.pdfIn PDF document text
    • http://vasekurzy.cz/userfiles/file/bezorisoxifaw.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/loo04tf9mpec5sm2uvoab5vnt0/loxasarusaluvuz.pdfIn PDF document text
    • http://vps73.juicy-group.com/editor_upload_image/file/mageligumisudonirunodafat.pdfIn PDF document text
    • http://www.jobibon.com/admin/userfiles/file/dizelafa.pdfIn PDF document text
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/s58eeqm1mu3e1je79c8ptmn6s5/88399291857.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/b6014d31008c1f789eb806e4bf94e067/zidexiwijetajerano.pdfIn PDF document text
    • http://caerulumpharma.com/upload/files/21780373100.pdfIn PDF document text
    • https://network-italia.com/file/32574714752.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+remove+unwanted+applications+from+androidPDF 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_off0000d4b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4B0 19424 bytes
SHA-256: 63be29a89557a25fb3b1068fe7a4c868be9db886e7da369203a9c2bfdfa1f22d
font_01_sfnt_off000106d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D4 11024 bytes
SHA-256: f6594333167824537c848fe5ebac2a386aee73eebff8aa1d18eda02e2440a390
font_02_sfnt_off00012078.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12078 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1