Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ac38a2b4f43fb8b…

MALICIOUS

PDF

71.2 KB Created: 2021-09-26 19:51:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0bfa40f795650384470b0290a238e417 SHA-1: c5aebb5dc8d93d8096d574b5c52c773d409544a4 SHA-256: 4ac38a2b4f43fb8b23fe0255d3a6fbe01a6fc7db565d9b3a76d37f9f0057816e
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://irlanc.ru/uplcv?utm_term=where+do+obb+files+go
    • https://abyway.lv/images/ck_images/files/regajaride.pdf
    • http://opuspointpartners.com/ckfinder/userfiles/files/kiritonanogiwiketudina.pdf
    • http://bharatdarshan.net/rgroup/ckfinder/userfiles/files/sigiziladepuzetotebovuk.pdf
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c8561a40f8---79513787997.pdf
    • https://pollackmihalyiskola.hu/ckfinder/userfiles/files/rixetowujo.pdf
    • https://papersacksfactory.ae/images/bulk_images/files/91050336831.pdf
    • https://eseninternational.com/uploads/files/37712389737.pdf
    • https://indicaperu.com/userfiles/file/vivewoxezuliposu.pdf
    • http://madonnina.info/userfiles/files/6043744950.pdf
    • http://rlponder.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xomelagojupikabug.pdf
    • http://bebelino.ru/userfiles/file/34422100232.pdf
    • http://ediljolli.com/userfiles/files/vifasodosimala.pdf
    • https://designmaster.in/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/lepolobuxaluritasowos.pdf
    • http://sancheonglittletheaters.com/upload/userfiles/2021/09/files/210911080042.pdf
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/leniderofeloloragetu.pdf
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161392b22e87b4---13823713132.pdf
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16132674eafd5e---firilokelorumedu.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613114048937e---kilixesebepagesifivire.pdf
    • http://harposwebdesign.nl/app/webroot/files/userfiles/files/xajanolomejozu.pdf
    • http://lnyuanzong.com/uploads/files/20210915155941.pdf
    • http://spain-ex.com/images/blog/file/leporulo.pdf
    • http://coytex.net/ckfinder/userfiles/files/89839221684.pdf
    • http://www.taxivanclass.com/uploads/ckfinder/files/zadisufekaxalukezobipe.pdf
    • https://speculatio.in/ci/userfiles/files/parigetewuxuti.pdf
    • https://vicareyou.com/userfiles/file/rabavalapupiporurogum.pdf
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1614ecb95afee6---vibamebamet.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b4ec.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB4EC 16792 bytes
font_01_sfnt_off0000ccfe.bin
aa04ccca2c06cbd66d46e8aed5233e2ad68cf95d8acf535903fa4e5cbc566a73
pdf-font-stream PDF embedded font (sfnt) at offset 0xCCFE 16888 bytes
font_02_sfnt_off0000f807.bin
eb4513f6c3030dfdbddd31ea9df6b8cf432a457af42a4acebabbc5196a39cf2d
pdf-font-stream PDF embedded font (sfnt) at offset 0xF807 10404 bytes