Malicious PDF — malware analysis report

Static analysis result for SHA-256 824e162f5a6ff862…

MALICIOUS

PDF

74.9 KB Created: 2021-06-12 10:28:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: b19a3c58b3d7e52e358e902d5faad327 SHA-1: 11f376cc77a6027648a48017d1d31c96a64db1f0 SHA-256: 824e162f5a6ff862f29e582626d5995f701e85e43977c5eb24b470f811e29575
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating it's a phishing or trojan delivery mechanism. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting, likely to redirect users to malicious content or phishing pages. The presence of multiple compromised CMS upload links further supports its role in distributing malware or facilitating phishing attacks.

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://krisoc.ru/uplcv?utm_term=the+monsters+and+the+critics+and+other+essays+pdf PDF link annotation
    • http://harasim.cz/uploaded/files/26792999933.pdfIn PDF document text
    • https://simondaulte.com/ckfinder/userfiles/files/jelaxegiwupilaz.pdfIn PDF document text
    • http://www.elitagida.com.tr/wp-content/plugins/super-forms/uploads/php/files/0sv6a3942m65nnk1ci6bdbtlv2/43754797466.pdfIn PDF document text
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/0dd8f4133ec3f45e7cc51349a27f90ed/91492688842.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160810381aff0d---tizobafitufonugukifelog.pdfIn PDF document text
    • http://olgapolyakova.com/files/files/76060486961.pdfIn PDF document text
    • http://willbramephotography.com/2045875449.pdfIn PDF document text
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160830d5fb940b---munimi.pdfIn PDF document text
    • http://katachizu.com/img/news/files/favenagunuzuv.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609d9e747fb91---duwuwokixaloponatute.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ae0e49d9e1e---21572154322.pdfIn PDF document text
    • http://stardentalcare.org/userfiles/file/85026753496.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608119fccb364.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079e1b1456a5---62616630222.pdfIn PDF document text
    • http://herculesestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/dupiselaxu.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/n81j98f521qn8rgbeuekdr6fl2/dadipesukeganalagi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7A5 5416 bytes
SHA-256: 3aba25b28c6a24e76126a6ac7cd0509e0cfffeadab520c18038242c2c9534ecd
font_01_sfnt_off0000f9ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9EC 10748 bytes
SHA-256: 28669841a64896a81e2c94ed3454076edef0f3e836bc30195f71f604fbf02e0a