Malicious PDF — malware analysis report

Static analysis result for SHA-256 251e9c6d46f0c5b2…

MALICIOUS

PDF

86.2 KB Created: 2021-06-30 23:00:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 17c9aaf1123f0a78ba26bbf9e966074c SHA-1: 3d92740220e34dfd3bb2033cd4d69b03b3093731 SHA-256: 251e9c6d46f0c5b249875e878a07db510fbecbfaba8a95609fcce597e207fb38
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous embedded URLs pointing to compromised websites, many of which are hosted on disposable domains or utilize WordPress upload storage. The PDF structure suggests it functions as a link farm, directing users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://medvor.ru/uplcv?utm_term=how+to+write+diary+entry+for+class+6
    • http://alkanboya.com/files/file///17618141696.pdf
    • https://www.prestigeautobody.com.au/wp-content/plugins/super-forms/uploads/php/files/a88cfeb4619687c48fbaad498b89901e/gilir.pdf
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607714a3405d5---rajisumanegodarowe.pdf
    • http://gld-lining.com/user_img/files/xisorelowafogub.pdf
    • http://charivne.info/images/file/99834725690.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160963748d02ff---pobetelajipedepiv.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607744ce9e477---62896449993.pdf
    • https://szallas-karpatalja.com/upload/37736026109.pdf
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/8e18b0f02f3652cec2b1b2284915c716/gaparomeduviju.pdf
    • http://xboxheerlen.nl/userfiles/file/rigananetudizodakekak.pdf
    • http://ministerium.pt/files/82236480475.pdf
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/1d6146ada34a71c689f2525d7663f72e/nabafakajanofujufakeg.pdf
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/1f9549b3841e2658193d730e1b6a0100/8532607678.pdf
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/adab75ac1bfc98cec2674e8433f6e9a5/gobitejanademamitipidi.pdf
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a90a5c85aea---xixafewelevu.pdf
    • https://ctapigroup3.com/contents//files/junarogikomupefaruneji.pdf
    • http://ccswcd.com/userfiles/file/pilikapamuto.pdf
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/9llgno6dhq9m3evt9onnb38s74/bokuxesusi.pdf
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/b9c82a2367909aa166f1b84fdf417505/55611597658.pdf
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/803bd335c88d3d1016f7bff6d353515c/soxopig.pdf
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/rjjgh9slvgu8nnf0um0b0k3cjh/15367387509.pdf
    • https://ukdirectremovals.com/wp-content/plugins/super-forms/uploads/php/files/2433587a4bc5220731ac9b0a6f6ce520/85021562849.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee8a.bin
79e13ef9706560ffc5d352abab50b1bc0d9c4df86e90bce68ca5985f737ebc3b
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE8A 16944 bytes
font_01_sfnt_off00011a30.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A30 16792 bytes
font_02_sfnt_off00013247.bin
92a0c88cc1f072333b9e448cf67e0b2a0349c1bb488fecde0ab1e0c69a84be8f
pdf-font-stream PDF embedded font (sfnt) at offset 0x13247 10828 bytes