Malicious PDF — malware analysis report

Static analysis result for SHA-256 2499220c3961e3f2…

MALICIOUS

PDF

76.0 KB Created: 2021-09-13 19:00:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 40fc2bb6276d937cce6d71f1f79c4fbd SHA-1: 18be11320f9f662e25828d4c6c3cee60d2966472 SHA-256: 2499220c3961e3f2002d7bcba8ba79e8562a4322e090f20d06e2625b05872776
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on potentially compromised or disposable domains. The presence of numerous PDF links and the 'utm_term_redirector' flag suggest an attempt to obfuscate the final destination and potentially engage in SEO poisoning or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://tsegypt.com/file/vumuvepomojen.pdf In PDF document text
    • https://path.mn/userfiles/files/49382841035.pdfIn PDF document text
    • https://coastalholidayproperty.com/ckfinder/userfiles/files/foguxupigixadas.pdfIn PDF document text
    • http://elencostruzioni.it/userfiles/files/lemifuwiroburuke.pdfIn PDF document text
    • http://onestep-tokyo.com/userfiles/file/92904281025.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f062e618dc---furekotegojumupelilukidex.pdfIn PDF document text
    • http://cbstav.cz/file/dubetoja.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/judafem.pdfIn PDF document text
    • https://clinicscrm.com/img/files/30194276289.pdfIn PDF document text
    • https://ip-pharma.net/data/files/73954542670.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/161322ea0742c3---48104839384.pdfIn PDF document text
    • http://traktor-tv.de/sites/default/files/file/wedotelumufuwexitewomi.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ec49c83bd5---17811394642.pdfIn PDF document text
    • https://vinaarc.com/app/webroot/files/ckfinder/userfiles/files/76161938982.pdfIn PDF document text
    • http://www.css-jp.com/upfile/files/2021/09/02/nezutekopasigenagunofi.pdfIn PDF document text
    • http://urbanconstructions.org/images/uploadedimages/file/musumemijekiselapavu.pdfIn PDF document text
    • http://mps-india.com/userfiles/files/29995420682.pdfIn PDF document text
    • http://www.optimizecost.com/admin/ficheros_fckedit_subidos/kelaxogefejaloti.pdfIn PDF document text
    • http://jlssj.com/qianzi/upfile/case_editor/file/rizaduriguxapoxopotox.pdfIn PDF document text
    • http://nj-rshb.com/v15/Upload/file/20219121437566613.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613cbb863e1e4---85672120676.pdfIn PDF document text
    • http://akvatoria.by/UserFiles/files/61738209041.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=como+liberar+ram+en+androidPDF 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_off0000c573.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC573 10312 bytes
SHA-256: 4d2b0678b801b38e01ae2a36d912acf40663e7c6f9ce93e82031ee9474b75c60
font_01_sfnt_off0000dc8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC8A 18252 bytes
SHA-256: a03e4bb593914ab2edf45e92c5da9d23cee0128b27254f1e8c423888aedd3e98
font_02_sfnt_off00010af9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AF9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1