Malicious PDF — malware analysis report

Static analysis result for SHA-256 1254b9cc3538ad9c…

MALICIOUS

PDF

98.1 KB Created: 2021-06-25 12:31:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 1d49728db95db4fdcec0a8b9c669d2b7 SHA-1: 7b154c63dfef3bef714a39a4b404151c3a7553f8 SHA-256: 1254b9cc3538ad9cac659fe433872d0e991cbcb34b18e9f385caa5208c3f060a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links pointing to compromised WordPress upload storage and disposable hosting, suggesting it's part of a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/8b3ce1f04d8759150553115b9ef4f491/korofej.pdf In PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/915um9s94qhbe2n0v0ekkq2a3g/16989017690.pdfIn PDF document text
    • http://khautrangkhangviet.com/upload/img/files/genodogimesemugos.pdfIn PDF document text
    • http://alamansyria.com/userfiles/file/sedejipibirimura.pdfIn PDF document text
    • http://ibiforstarlight.org/clients/3/3c/3cfcca4e360ca8807b7dd7d6e7cbeae0/File/40739345217.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/qdqpuipdovtj9ekpglfb3f1rip/85747960459.pdfIn PDF document text
    • http://www.elitagida.com.tr/wp-content/plugins/super-forms/uploads/php/files/lt4222hlcq5gp3lahvocqpqd74/meveda.pdfIn PDF document text
    • http://anhuizpyy.com/upload_fck/file/2021-5-10/20210510111312530731.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/d8386ca6ab61b83e71a86b6d38a9efa6/48382302704.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/945411332569202167f9c9c9e64be162/87996258972.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/5429c281dd822508416cb4305f29943d/lirijexageti.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607a8480eff7b---56633825152.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/337d0b6a8d632a71de0d066f756aeac1/8736024167.pdfIn PDF document text
    • http://vekosgroup.ru/userfiles/file/98218272771.pdfIn PDF document text
    • http://baovephuongtroi.com/vietkiendo/upload/file/42790930903.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/ca44d2402930554da5eb46336b07f591/82399828890.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=badminton+rules+and+regulations+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_off00011e96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E96 16804 bytes
SHA-256: 4d98bde1fcdcf77e5908ecf8c1a20296129f6419fb0e86964477f8a25bcd4546
font_01_sfnt_off00014a6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A6C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016283.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16283 10996 bytes
SHA-256: 98df87b46a47b825bba7fee3e9fa0a5a254bf0a190666cd656354a7cabdcd9ee