Malicious PDF — malware analysis report

Static analysis result for SHA-256 25f391c1516994f1…

MALICIOUS

PDF

113.4 KB Created: 2021-09-11 06:28:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 177b8b1a94701ef7f5fd38ad196cbbe0 SHA-1: 44a96741192f82c6f46eaf4c1e5dc5dc66067bfa SHA-256: 25f391c1516994f1f28f74c7af86f8a12a8a66ca447f28c3bf363bcd51b02ce8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the presence of a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to lure users to malicious sites. While no executable scripts were extracted, the structure and URL patterns are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://archism.ru/uplcv?utm_term=research+methods+in+sociology+pdf PDF link annotation
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135910b3da96---46619660419.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/a44cfc901637f65323d4de5454f99d34/jizejowemus.pdfIn PDF document text
    • http://alfonsoguiggiarchitetto.it/userfiles/files/gireso.pdfIn PDF document text
    • http://0985028898.kad.tw/kads/ckfinder/userfiles/files/bipezivorujinawofasosod.pdfIn PDF document text
    • https://immo-macedo.lu/userfiles/files/83451371279.pdfIn PDF document text
    • http://savoie-outils-coupants.com/ckfinder/userfiles/files/veliv.pdfIn PDF document text
    • http://nattuvaartha.com/assets/ckfinder/core/connector/php/uploads/files/tijiwobuwegeke.pdfIn PDF document text
    • http://shlawllc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/komeg.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/16132fa182916b---71509292943.pdfIn PDF document text
    • http://elateridae.com/images/FCKeditor/file/jazefitifulix.pdfIn PDF document text
    • http://kup-vino.cz/web/ckfinder/userfiles/files/fekadutazilozezafurexo.pdfIn PDF document text
    • http://finalbrand.cz/upload/file/duwamozujejepulilusujona.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-6/20210906100638211708.pdfIn PDF document text
    • https://2winit.com/Files/files/36576648891.pdfIn PDF document text
    • https://swalaya.in/userfiles/file/kogexelopabijavovuxi.pdfIn PDF document text
    • http://vimar.ua/userfiles/files/kivinureduzizozixalogo.pdfIn PDF document text
    • https://szallas-karpatalja.com/upload/ruvekalanamakepu.pdfIn PDF document text
    • http://saringkarnwood.com/UserFiles/file/35941690734.pdfIn PDF document text
    • http://suchanekstomatolog.pl/files/file/zirepa.pdfIn PDF document text
    • https://mdteam.se/ckfinder/userfiles/files/powuw.pdfIn PDF document text
    • http://abwjefferson.com/uploads/files/40652269822.pdfIn PDF document text
    • http://magooferta.pl/uploads/fck/file/jakokajatelowadorolo.pdfIn PDF document text
    • http://imbirimbir.ru/files/sexadibodoviduliruxez.pdfIn PDF document text
    • http://ybshajiang.com/userfiles/file/2021-09-06/210906094544022070bw8s23eggoi7.pdfIn PDF document text
    • 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_off000155bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x155BD 18840 bytes
SHA-256: 8cbf7e68bf57fdc86f526c2d70b9fab2e5b6d102a50fbc796f26178f3211c26e
font_01_sfnt_off000185f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x185F7 11228 bytes
SHA-256: b03bbaae7379d7d0a85025198dc1f93130fe64baea81bb897baf5919e162e5c8
font_02_sfnt_off00019ff0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19FF0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1