Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5c7a400d468fe90…

MALICIOUS

PDF

89.1 KB Created: 2021-06-28 22:31:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 535b8d8b985746a69c1de1d16380a580 SHA-1: bbef527a82f635d4d0d2b78732da1eabf6bf9fc8 SHA-256: f5c7a400d468fe904a2bbfbb8769e3c00f09ee65c38e6881477f760efa24b335
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or directing users to malicious content. No scripts were extracted, and the document body was unreadable, but the heuristic findings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://stratasphere.online/userfiles/file/47106051094.pdf In PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/a005afcc552a0fc4b434af1bc59e63e3/69003786625.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b1d77bb5c---surapelamaxit.pdfIn PDF document text
    • http://kassa.pl/userfiles/file/36901364709.pdfIn PDF document text
    • http://haozuowenwang.com/imagefiles/file/2826553341.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/160944a5792e0d---40698621860.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/lp8b41gdd0op7s1kg2pbid7985/depevukowanotexezanus.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b57e560d36c---zadarasokevut.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d65e85c08ce---wadojaxalisi.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/f2ff3e63df8d0baf842492b917a9d8a3/kokotapunobo.pdfIn PDF document text
    • https://salubrismd.com/wp-content/plugins/super-forms/uploads/php/files/ec4dd3475e212163ce4793cf1bf7b314/losalajoporogaragopajuva.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/1c0144821a67d11f477c088d086db3b3/70751440354.pdfIn PDF document text
    • http://nieruchomosci-swidnica.pl/userfiles/file/4974001786.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc01b61ce9---68768778325.pdfIn PDF document text
    • http://nirmalamathachurch.org/cms_uploads/image/file/25073368442.pdfIn PDF document text
    • https://beltamas.by/content/Files/wudutadugevebowasabud.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/94597a59da9829ac2d6c7cf39582ee06/87434451708.pdfIn PDF document text
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/0fomnd0hcvog75iv0psteuldvl/wigapa.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/3cbb07ddb0fe1e9097ab9ce24c81a4a8/5036062125.pdfIn PDF document text
    • https://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/498cb23d869349370623ee0289e6a594/nazapevelij.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae48ed45bcb---36094265196.pdfIn PDF document text
    • http://qtjdb.com/UploadFile/2021/06/28/file/20210628_212117_111.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/e107bbdd564c2ff630fc53bda962d076/83265731776.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=the+virginian+welcoming+townPDF 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_off0000f967.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF967 17428 bytes
SHA-256: 351f9057abe4b99c119be4c880a3cf8b6d94c4668c2d2f82215fe7aae06de3e5
font_01_sfnt_off000125a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125A7 10624 bytes
SHA-256: 9e2892534b459598660dfd7e49554c3f2ee289fce496421250085a3d6725bff0
font_02_sfnt_off00013dd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DD8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1