Malicious PDF — malware analysis report

Static analysis result for SHA-256 2667efb5b09fa2f3…

MALICIOUS

PDF

85.0 KB Created: 2021-09-23 17:03:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 928236eda7dbdfb83153677361f8c32e SHA-1: f379dd8befaeda0587760a8cbf5ebf4df7812141 SHA-256: 2667efb5b09fa2f32e0a30d2e29483527e4a6662e78193523e2ebc2396a53e15
156 Risk Score

Malware Insights

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

The sample was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised CMS uploads or are part of link farms on disposable hosting, indicating a phishing or malware distribution attempt. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically highlights the nature of these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://galluccifaibano.it/userfiles/file/57412033238.pdf In PDF document text
    • http://gildiamasterov.ru/userfiles/file/31838236699.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/5q6cgk39vlemoomqlojl12o316/56806792428.pdfIn PDF document text
    • http://anshan56.cn/userfiles/file/16323919061990778044.pdfIn PDF document text
    • http://hamlineparkplaza.com/assets/amund/ckfinder/userfiles/files/fijinawulelorikajun.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ffff02beb8---ravav.pdfIn PDF document text
    • https://lifecareproduct.in/ckfinder/userfiles/files/sazevegoxividuzomezuziji.pdfIn PDF document text
    • http://www.clc-engineering.com/siteuploads/editorimg/file/vibemixazifa.pdfIn PDF document text
    • https://pasationtravellers.com/root/FCKeditor/file/miwezopilewazofumituvemis.pdfIn PDF document text
    • http://morgancountyoh.com/userimages/sivetejiberaz.pdfIn PDF document text
    • https://sealordhotels.com/ckfinder/userfiles/files/16867686969.pdfIn PDF document text
    • https://juhaszautovill.hu/userfiles/file/6705467618.pdfIn PDF document text
    • http://tecksco.com/upload/files/7502338669.pdfIn PDF document text
    • http://urs-certification.com/gais/image/file/xuzojozu.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16149d1f54e5ca---numefunuweledazuwunosod.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c77b30960b---91915646880.pdfIn PDF document text
    • https://spirit-legend-enterprises.com/webroot/editor-uploads/files/marubixujibit.pdfIn PDF document text
    • http://mcutech.net/files/33993271801.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f83e387082---41905537471.pdfIn PDF document text
    • http://studiofelician.com/userfiles/files/21497601565.pdfIn PDF document text
    • http://pharmabiosolutions.com/filespath/files/20210919203648.pdfIn PDF document text
    • http://novastal.pl/userfiles/file/wuseletudepozogunagul.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/gazejafeginukokedoz.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/0f04d0f6de2953a2380a4f96ed653a32/13911390234.pdfIn PDF document text
    • https://oriental-kitchens.com/userfiles/files/69088926573.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=system+ui+keeps+crashingPDF 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_off0000e63c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE63C 11036 bytes
SHA-256: 023506b59365bd910f82e0a7fa7f28c26fdd134f1b552b627a6fba643fbf428e
font_01_sfnt_off0000ffc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000117d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117D7 17968 bytes
SHA-256: c3c78ad85777078aa17bcb668ed3446a41dd1762b7e873e29db0e0fb1ebe7c2f