Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5d6788e108e8644…

MALICIOUS

PDF

84.5 KB Created: 2021-06-27 15:20:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 1d62ba36043db9a7118af257572f985d SHA-1: 37e2840c437489d2fb1daaeba1ec62d46e09db4e SHA-256: a5d6788e108e86445a0de11c7c64d4a9c6c46f49a13ab3ae05ae899eda6ace3e
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised CMS uploads and other domains, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment that it is part of a phishing or malware distribution scheme. No scripts were extracted, but the extensive use of external links is the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://coretry.ru/uplcv?utm_term=find+the+reciprocal+of+5 PDF link annotation
    • http://akkoryazilim.com/userfiles/file/56476570269.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/16077647b813eb---41952657537.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/nilorovizu.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160863197c95e5---4009226994.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a0296e2352d---29935770701.pdfIn PDF document text
    • https://www.visitrwanda.com/wp-content/plugins/super-forms/uploads/php/files/c18db6e034f56c494209014012462573/sizunoxejesiroruji.pdfIn PDF document text
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/42c780c19d989d5a42c84771be3ec963/kaseg.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082b6d0b2c8c---tezozijuzomajavitozifa.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16085d8b93cdfe---pikiwomeza.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c55eba10d97---11731084972.pdfIn PDF document text
    • http://hccc252.ca/clients/e/e4/e484b38507f190a955b66748903449e1/File/75318883693.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c5b74fc7fb4---zivenakozil.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/e46e78dd2ca3cine04oo4ih07p/rugipuparilegojex.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1608900a8df3b4---sabefusej.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d942c227e0---66915990056.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cf78b6983ef---zuriwutivemisojez.pdfIn PDF document text
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/b9e914bf3509d4cf4577fce0685d060a/zodotelufinometuvu.pdfIn PDF document text
    • http://cropscipublisher.com/files/upfiles/file/vazurikapu.pdfIn PDF document text
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/443df68345c039fa00c72409cd0770ba/19259749632.pdfIn PDF document text
    • https://iword.de/userfiles/file/26807327159.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/74af9e372552ff8faa05d178a2d010b7/lividif.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/22897199250.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ccaad190ba---dekovag.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5d8e5e64db---kijoma.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_off0000e5a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5A0 17820 bytes
SHA-256: 40e5b9aac8f64a6b179fb806226cd7df625738a5a93b84bff403186049c4ed6d
font_01_sfnt_off000114b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012cc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CC7 10660 bytes
SHA-256: 3cedead094d04c1ff3fb66215802acc1f26f87355063f2f4bedbd3a8cf6f7004