Malicious PDF — malware analysis report

Static analysis result for SHA-256 523db9dcc86ee0ce…

MALICIOUS

PDF

81.1 KB Created: 2021-09-04 15:05:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 372852676c35066551ab8a25a99b200b SHA-1: e1e79eb1ce3e27e9fbe4e24b94fb8b13871d24ce SHA-256: 523db9dcc86ee0ce51bf29035fa605c6489c50b69231175f85cd49996a28c020
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It contains numerous links pointing to compromised websites, suggesting a phishing or malware distribution scheme. The presence of external URI links and link farm patterns indicates an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160e44d25baa00---14626232776.pdf In PDF document text
    • http://netflor.pl/upload/File/watudibuxizozonenejem.pdfIn PDF document text
    • http://preciz.com/uploads/wysiwyg/files/65558958821.pdfIn PDF document text
    • https://habibitoursegypt.com/ckfinder/userfiles/files/90335191085.pdfIn PDF document text
    • https://feltshoe.com/userfiles/file/93224343280.pdfIn PDF document text
    • http://leinerpakgelatine.com/survey/userfiles/files/lowapu.pdfIn PDF document text
    • http://exosportsante.fr/ckfinder/userfiles/files/51891079620.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607b1fdb78292---42036274877.pdfIn PDF document text
    • http://duda-tech.pl/dudatech/upload/file/62518514175.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/74165915172.pdfIn PDF document text
    • https://melz-feu.ru/upload/81965373257.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c784b8772b2---85714803569.pdfIn PDF document text
    • http://cjatkinson.com/userimages/wavil.pdfIn PDF document text
    • http://centralcogtc.com/uploads/file/77565653821.pdfIn PDF document text
    • https://ski-experience-japan.com/images/blog//file/18130401383.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cbd801678a2---87374497083.pdfIn PDF document text
    • https://sokolzgierz.pl/web/uploads/files/81160925605.pdfIn PDF document text
    • https://makanbanyak.net/contents//files/sekus.pdfIn PDF document text
    • https://aynadakikemalizm.com/resimler/files/pavuwexitodopabovaruzi.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1607978fc121c6---7123582579.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=fetal+circulation+diagram+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_off0000d889.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD889 18028 bytes
SHA-256: 3c2e708e081c90192633aa75517aef9a9af71357cc039ac45e35ac8e3586dc95
font_01_sfnt_off0001069d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1069D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011eb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EB4 10872 bytes
SHA-256: 841b0b598b5461a59d6313cb0e6e1a032da09e0ad8178b6ecaab7a21fb0c9f6e