Malicious PDF — malware analysis report

Static analysis result for SHA-256 85657535eb3108f5…

MALICIOUS

PDF

78.9 KB Created: 2021-09-21 15:04:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 4cbe259251d0f29f5251b694e1bf6b41 SHA-1: f6bf974bdbca2758c32100df79f42f66292d6c96 SHA-256: 85657535eb3108f5f4efe496f154eb68e7187e1a973753c98ccd90f49baec053
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. The presence of multiple links suggests an attempt to distribute malicious content or redirect users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://archism.ru/uplcv?utm_term=dream+league+android PDF link annotation
    • http://maximaviajes.com/FCKfiles/file/55523518106.pdfIn PDF document text
    • https://medicabg.com/uploads/wysiwyg/files/pulizovixapi.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134f959b034c---4838305063.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/mabewenuzipefizuruvobiwa.pdfIn PDF document text
    • http://oembag.com/uploads/files/202109190412153293.pdfIn PDF document text
    • http://boldogelet.hu/media/pofidobimuwesemox.pdfIn PDF document text
    • https://zlato-eu.cz/upload/files/lebivam.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/549e4710d98437fd56f727b4af2c7ca3/xisafa.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cad4ce0859---levuwexuxunilotagabis.pdfIn PDF document text
    • https://vresponse.net/userfiles/file/51419803978.pdfIn PDF document text
    • http://woykoff.hu/upload/file/gefuvuwagodolawega.pdfIn PDF document text
    • https://karolinanowak.com/userfiles/file/74644704515.pdfIn PDF document text
    • https://safewatersolutions.in/ckfinder/userfiles/files/29984363857.pdfIn PDF document text
    • http://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/gutolegumivuk.pdfIn PDF document text
    • https://peoplesmodelinternational.com/ckfinder/userfiles/files/2759596432.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/99356373994.pdfIn PDF document text
    • http://parateam.cz/file/24839620079.pdfIn PDF document text
    • https://eledigitalpr.it/allegati/file/xusoxuxugefomoboze.pdfIn PDF document text
    • https://topconta.ro/userfiles/file/bokigan.pdfIn PDF document text
    • http://sor1310.com/userfiles/file/6146464712.pdfIn PDF document text
    • http://ipceurope.eu/assets/file/74042104170.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_off0000cf7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF7B 10428 bytes
SHA-256: b06a37cde31640968344a54fd5aa73c2a04c0abae5f8e91c00997bfdc2d533f0
font_01_sfnt_off0000e6be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6BE 18272 bytes
SHA-256: ea5937ba898b7f65f94ae80ba1b8b2880d07a5b99e8843417c213381972404a3
font_02_sfnt_off00011666.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11666 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1