Malicious PDF — malware analysis report

Static analysis result for SHA-256 d2859519f279d5b4…

MALICIOUS

PDF

88.5 KB Created: 2021-06-13 15:31:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 37ee0c2943e5d17d382946588902ddf3 SHA-1: 42f63ca0ff22c7e0ed2de7ec692f9306cc8c6864 SHA-256: d2859519f279d5b4b8d39cb7dceafef65b7602fbb2424bfba18de42910bb1ad8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous embedded URLs pointing to potentially compromised websites, suggesting an attempt to redirect users to malicious content. The PDF structure and embedded links are indicative of a link farm used to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://crysiq.ru/uplcv?utm_term=role+of+teacher+in+21st+century+education+pdf PDF link annotation
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/ltot0gjs5dm6muc7s5dmbivifa/kafulafozazonivowu.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160946630d310d---gexeremuz.pdfIn PDF document text
    • https://abe-rdc.com/userfiles/file/sebawolijirikelasoz.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/mfgi026cs4hcfij8m1u0kp2bum/naratisariwiwiwezebak.pdfIn PDF document text
    • http://birzebbugastpetersfc.com/files/file/70063857864.pdfIn PDF document text
    • https://hotelindigha.com/FCKeditor/file/99052744175.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/28577114534.pdfIn PDF document text
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9c8491272---firipojuxesa.pdfIn PDF document text
    • http://kpdb.org/userfiles/files/72935751489.pdfIn PDF document text
    • http://ambulatorioveterinariorigolon.eu/userfiles/files/tegimenifok.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608b6731ef117---85333618097.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16084b1b9e2ea8---59389655242.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/17972a2c3aa2665bc2976bae1f5712a7/kitisenelasiro.pdfIn PDF document text
    • http://allnatureint.com/userfiles/file/16895671262.pdfIn PDF document text
    • http://kaies.cn/upfiles/file/73168015824.pdfIn PDF document text
    • http://animalscipublisher.com/files/upfiles/file/pujotaja.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010c98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C98 5416 bytes
SHA-256: be725ff39d9f80931130608b89f7a5d51e5951b078f92f5816d1b23a2c28ac21
font_01_sfnt_off00011f09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F09 10932 bytes
SHA-256: da4bec100a851eb5503c7317f26490b5e46ee366b4143e8ee1b162565e4e8e40
font_02_sfnt_off00014455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14455 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34