Malicious PDF — malware analysis report

Static analysis result for SHA-256 e33a564af42fd486…

MALICIOUS

PDF

75.8 KB Created: 2021-09-17 16:00:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 43780f091e72d13c8801d6f3e9cafa8b SHA-1: f015457fc6f65f2a51bf814569e4a51e0563f8c3 SHA-256: e33a564af42fd48654bada88a4906c6305493888dea071351efda403240aa4d4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics as containing a link farm on disposable hosting, with many URLs pointing to compromised CMS uploads. The ML classifier and ClamAV also identified it as malicious, likely a phishing or trojan delivery mechanism. Although no scripts were explicitly extracted, the nature of the link farm suggests an attempt to lure users to external sites for further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://limpiezasinasel.com/userfiles/files/kiduxa.pdf In PDF document text
    • https://jgranit.pl/userfiles/file/85283968942.pdfIn PDF document text
    • https://oolong-dining-co.com/webroot/editor-uploads/files/pemekomukemivitim.pdfIn PDF document text
    • https://ndmoyun.com/calisma2/files/uploads/widemizugemabijezozo.pdfIn PDF document text
    • http://realtor-madrid.com/uploades/fckeditorfile/pevanobexopomemi.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/16133b6e4c4c60---jebajiwalanojaxefade.pdfIn PDF document text
    • https://autonoleggioassereto.com/file/98997727611.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/16137d34287dc0---32119221107.pdfIn PDF document text
    • http://gokea.org/upload/editor/files/62769781317.pdfIn PDF document text
    • http://bibliotekaszamocin.pl/img/upload/files/xizukajokadavugi.pdfIn PDF document text
    • http://drzwiukryte.pl/userfiles/file/xikuvu.pdfIn PDF document text
    • http://tjtvina.com/Upload/files/jubaduxezozanemilegiwizo.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161439fe80b15f---49093996239.pdfIn PDF document text
    • http://abwrosedale.com/uploads/files/4589231764.pdfIn PDF document text
    • http://tajeer.co/userfiles/file/67947410332.pdfIn PDF document text
    • http://alpha-cp.com/userfiles/file/58236509397.pdfIn PDF document text
    • http://hunicorn.hu/userfiles/file/25883081916.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/974037a42c674e661fcf619e0afce3f3/80423683790.pdfIn PDF document text
    • https://imaggu.com/ci/userfiles/files/20544836203.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/11592050618.pdfIn PDF document text
    • https://globalcareerclub.com/FCKeditor/userfiles/file/wadekaragelatebezibajam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=gamepad+vr+apkPDF link annotation
    • 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_off0000c4f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4F3 10120 bytes
SHA-256: d469222cf17212bf8828537d41b3cce93ad925e7ad797b4fdc08ec329e3b1e7b
font_01_sfnt_off0000db89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB89 17812 bytes
SHA-256: cb1df408cd9d7b82891d4546dbd0e35b07d8c2c7aba10f85540538c638a8ff9b
font_02_sfnt_off00010a44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A44 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1