Malicious PDF — malware analysis report

Static analysis result for SHA-256 864d6668e397a9e4…

MALICIOUS

PDF

79.9 KB Created: 2021-09-06 11:10:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 4fe6fa68cdf98325d70b53e2f30cef2c SHA-1: b5ab0e42799d167161c43a8c6a288f9b1406ce27 SHA-256: 864d6668e397a9e484dcbf75f5c792c2a5af41cd76c0074b4b79ee3bbf020c4b
96 Risk Score

Malware Insights

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

This PDF document is identified as malicious by an ML classifier and contains numerous links pointing to potentially compromised websites. The heuristics indicate it functions as a link farm, likely intended to redirect users to malicious content or phishing sites. The presence of multiple external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest an attack pattern focused on driving traffic to attacker-controlled infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • 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://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/5e418b414a082b521b61ac0beda839a6/94779595702.pdf In PDF document text
    • https://mfdesign.hu/files/file/94359618619.pdfIn PDF document text
    • http://pazarziraat.com/userfiles/file/lupesewelamupabufekoda.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d319471d29---92500497397.pdfIn PDF document text
    • http://bowenlawmt.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/58139331826.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c459b88ae7---lutivevosudevibusejozadi.pdfIn PDF document text
    • https://marbellamohali.com/wp-content/plugins/super-forms/uploads/php/files/bbb5dbe7bd234ca370d377c0d5b45d34/15270080306.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1610f2150bc3d8---jukopesufi.pdfIn PDF document text
    • http://cariboohose.com/userfiles/file/26721044392.pdfIn PDF document text
    • http://tunapvietnam.thietbiotoviet.com/Images_upload/files/tinisanu.pdfIn PDF document text
    • http://www.aamuhsv-madisonalumni.org/files/files/29457244036.pdfIn PDF document text
    • http://identik.hu/editor_up/sasefesubifafawuraju.pdfIn PDF document text
    • http://www.reenactmentmarket.eu/images/wyswig_images/file/56920150302.pdfIn PDF document text
    • https://easybuildapp.com/files/uploaded/files/94206304232.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/12141728965.pdfIn PDF document text
    • http://stauarchitetti.eu/userfiles/files/42634298693.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/20219522504840.pdfIn PDF document text
    • https://iword.de/userfiles/file/43115019775.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/69660092759.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1612b64bfe80a1---xojabosifabigiv.pdfIn PDF document text
    • https://zlato-eu.cz/upload/files/16902119270.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/jhj6pka70kgeq0imamicsf7bmi/revavosevatiripi.pdfIn PDF document text
    • http://fw-simple.com/uploads/files/fexet.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=passive+haemagglutination+test+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_off0000d562.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD562 16572 bytes
SHA-256: fd705e34cb3861b8d7e25e70339304c815ef8c11bd4ff121955184c435a4366a
font_01_sfnt_off0001005b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1005B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011872.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11872 11012 bytes
SHA-256: ddbb5ced2e09a09988f44c56153b96c073c24ad836e4d5608f9a0ab4ba23a954