Malicious PDF — malware analysis report

Static analysis result for SHA-256 658f2ad358db13f0…

MALICIOUS

PDF

69.9 KB Created: 2021-05-28 21:00:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 578173733d435f2053c81dc8ad403888 SHA-1: 46c1543821a98882b3dfb51e061c13af88be0d2c SHA-256: 658f2ad358db13f062f91d933e927ccb97401710b3ff6f36ffe670d2b29eb825
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing attempt. The document body, though heavily obfuscated, suggests a lure related to academic assignments. The presence of numerous links pointing to compromised WordPress sites and disposable hosting reinforces the phishing and malicious content distribution intent. No scripts were extracted, but the PDF structure itself is likely used to host or redirect to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/p9d2i2slgfdf6e2og9r7sf4reg/15681973626.pdf
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/90up3nmuids7o7qsp70jtng03g/zanekafe.pdf
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/596blfm89453ue28epm1tjfa1d/debobozetuviduzele.pdf
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160980f0f0374e---3488113322.pdf
    • http://kpdb.org/userfiles/files/jafapimuvo.pdf
    • https://etonbio.com/newsLetters/images/file/xajusaduvibenekaxasato.pdf
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/7ef4d14a156e7bbe74075026e2211311/nufapitoze.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc7e7a578e---82001766975.pdf
    • http://aelma.com/sites/default/userfiles/file/nitovinikilukupab.pdf
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d7ec1cdb64---pafepimesonitekodajipe.pdf
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e788e2927c---tiwasefonozamupuwed.pdf
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a9f875c6db---53737698811.pdf
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075fe6440d15---82124604581.pdf
    • https://hgb.se/filer/file/nepowerexinekazo.pdf
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160908c78c4efd---63556608626.pdf
    • http://tunglamgarden.com/images/fck/file/53998501003.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a92755a40e4---52388561485.pdf
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160776cbf51f86---20294970474.pdf
    • https://inncredel.com/uploads/63862893396.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=aiou+b.ed+solved+assignment+autumn+2020+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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d3fb.bin
04f411871b49a1f2f4658cf800e47f8c04faf7a89a5adcf390b84ae06f59be85
pdf-font-stream PDF embedded font (sfnt) at offset 0xD3FB 5760 bytes
font_01_sfnt_off0000e795.bin
17c73bf5e525614bf281d833b8cf7cc2d32370c78a4a10f48dacc945c2096389
pdf-font-stream PDF embedded font (sfnt) at offset 0xE795 10132 bytes