Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e3f89f020346901…

MALICIOUS

PDF

90.2 KB Created: 2021-06-26 14:44:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: b1e333ca736afbdad1142ac186ff1be8 SHA-1: 8c49c978be7f5463b2d04d3caedcf1d0fe2b7bc4 SHA-256: 3e3f89f02034690183e889e37e2a0c07ff7550dd0f440a564903ecf1d192d8f3
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating a malformed exploit stream and a link farm pointing to compromised CMS uploads. The document body is heavily obfuscated, but the presence of numerous URLs, many hosted on compromised WordPress sites, suggests a phishing or malware distribution attempt. No scripts were extracted, but the PDF structure itself is indicative of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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 http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607c25240339e---40701532061.pdf In PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/3dd8ea4c95cf79c533e3a77c93aef193/43578563545.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf0a337c32---93000795726.pdfIn PDF document text
    • http://classicalgardenornaments.com/uplds/file/tatavifofuzi.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16099cf0cbdd7c---85766451485.pdfIn PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/8c3840e74ed4e616aaf5a90cf3e50246/jawidubufopegejamifo.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/0c8083b872b3c945a9ebe6958b69f3a8/satobalezukotinivo.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/a4tsmraebtd9sv3uirons1u0bq/46073325748.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/96ui7epuivjbirec0fqnc18k96/verep.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/160b75d9c8020f---37390105241.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c8da2a16139---zulifirojusawo.pdfIn PDF document text
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/d490313e9b2afb8c43dbb97c00f28942/nixifazuluperobib.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160868581370d7---gunok.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16070f539019c0---79150250228.pdfIn PDF document text
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607325451deeb---fonujuxopogiropuroluw.pdfIn PDF document text
    • http://tz5168.com/uploadfile/image/2021/06/20/file/20210620_154301_103.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609a41e366536---45391892242.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c61ce888465---fapimarulibe.pdfIn PDF document text
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160a58f73d2dfe---42210113119.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609216c0636d9---fexanunovelogebozoxutiso.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/5anghmd1d2kcs6hqpj8lf40v2n/16571092883.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd4abb6748---1577349593.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/1j9b12ki57k5q8blaro352jiup/sorijedogejoxobonelam.pdfIn PDF document text
    • http://daoltrading.com/userData/board/file/45117903181.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/86473193270.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2375fd7f85---36766136269.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=recommendation+letter+from+client+to+contractorPDF 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_off0001005a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1005A 10512 bytes
SHA-256: 1fac26259cf52234d1b1be0af7a84260e845202615a1576bc9184553805169af
font_01_sfnt_off0001183a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1183A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001304c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1304C 16584 bytes
SHA-256: c3bd6f7afe4b6850048e08c259389845a66a6f5ee80eaa03beab3fc026093de0