Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fa6f37000f941fd…

MALICIOUS

PDF

87.0 KB Created: 2021-07-06 12:11:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 702134e8ec0b5abcb03bb49c0d5ffa16 SHA-1: c49ce6f8d5b0f2f3dc5094468821d1c439cb6aee SHA-256: 3fa6f37000f941fd9f53b3ee4cfe0aa474e2b132efdbe6e0b909f7d66cecdc2f
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm hosted on compromised WordPress sites, with numerous URLs pointing to PDF files within plugin upload directories. The presence of 'utm_term' parameters in some URLs suggests an attempt to track user engagement with these links, further supporting the phishing or redirection lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16087c941b4986---nexiwepewi.pdf In PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/0ceb5707cdf9031ad0119f759d1d5195/belolevekudu.pdfIn PDF document text
    • http://kleinschaden.expert/userfiles/file/ruwuzuziropitukuzawa.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/ml8dsoqvcfv125k9jfslbrl1ol/fevuf.pdfIn PDF document text
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/ef97b7a600bbfaa9a4ace1b01504d226/66005945488.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ce78a0e0c24---37152899145.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16095add8aaa64---keruza.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607d533e7cf9a---xadubizawafewefikakaju.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2cf5315b50---20937048608.pdfIn PDF document text
    • http://izumrud38.com/ckfinder/userfiles/files/nokusazevirazilikinadom.pdfIn PDF document text
    • https://glaze-metalart.com/upload/files/33319521622.pdfIn PDF document text
    • http://zonweringbelgie.eu/ckfinder/userfiles/files/91177909098.pdfIn PDF document text
    • http://geoodwierty.pl/files/file/sovabuzotedezajirimadesaf.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/11817573273.pdfIn PDF document text
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607e91887a640---97019011506.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16082ae89cea48---92199211917.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6752cfa3f---29982573136.pdfIn PDF document text
    • http://barrybusiness-crm.com/ressource/devis-photo/files/2920986465.pdfIn PDF document text
    • https://partner-support.net/user_data/userfiles/files/52572252711.pdfIn PDF document text
    • https://paymentor.nl/uploads//file/lirorol.pdfIn PDF document text
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/74ab47bc550e56b060fa0069a49b9e87/rumipevegilupe.pdfIn PDF document text
    • https://girilawfirm.com/content_files/files/23017890128.pdfIn PDF document text
    • http://tikatalog.sk/_files/file/65365323841.pdfIn PDF document text
    • http://bsbcarpet.com/userfiles/file/litewasoronoduwoji.pdfIn PDF document text
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/ae4e76828710e5b52ed2c629d86b9326/xakuxipudilekabi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=in+the+wee+small+hours+of+the+morning+frank+sinatra+lyricsPDF 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_off0000eed1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEED1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000106e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106E3 17452 bytes
SHA-256: ef46346befe91c5cfff8485d577ff31d9d12e144721da00c819ce1914ab75eb2
font_02_sfnt_off00013422.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13422 11124 bytes
SHA-256: d028937a58066182f7b4c5fc06b287d0037ec8d90bab1f0fcc823f134f6b48af