Malicious PDF — malware analysis report

Static analysis result for SHA-256 2639285c455a7116…

MALICIOUS

PDF

83.0 KB Created: 2021-09-02 10:46:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: db0843dc47e1e7ff808a1e100736341c SHA-1: 7a655104473eba4f80bacd5d8ab69efa50c03afe SHA-256: 2639285c455a71162a70b11e065cbc7ff0a7d3917633da7e0801aa54cece28b6
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress installations. These links likely serve as a link farm to redirect users to phishing or malware distribution sites. The use of compromised CMS uploads and disposable hosting suggests an attempt to obscure the true malicious infrastructure.

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 https://queure.ru/uplcv?utm_term=steaming+mussels+in+wine
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160737e2ff09b3---33798323651.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/7ab54ca545194cfbf33abf2e631cb762/75104477693.pdf
    • http://101-games.ru/images/uploads/files/52870806582.pdf
    • https://rittenhousesmiles.com/wp-content/plugins/super-forms/uploads/php/files/453bbf7e65f0d2dab1279d7ae78d2a9b/42903677432.pdf
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/6cf03563cf628fcdae7057dae4967edc/52008095283.pdf
    • http://josephfellerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/30422509939.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a34eac6de05---33101716106.pdf
    • https://www.babetravelling.com/ckfinder/userfiles2/files/tupeveju.pdf
    • http://dieta-plus.pl/userfiles/file/7812395941.pdf
    • http://chi-kara.net/userfiles/file/guwetolexalela.pdf
    • https://szamitogep-szerviz-javitas.hu/ckfinder/userfiles/files/jatopizevodalularum.pdf
    • https://europacreativaeuskadi.eu/files/galeria/files/zixedipagisemufarab.pdf
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/d2d8646341ca65c409c8f4c1ff20e5c8/kuxazumejururivum.pdf
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f75fa7aa70---84273333302.pdf
    • http://ypperfect.com/ckfinder/userfiles/files/dixujar.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16073d796edaa4---88931362502.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607d5a71b3e49---dowodisufob.pdf
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/2919dad70db95976cbac5fa145412aec/92591981414.pdf
    • https://soechi.com/userfiles/file/tidojituloridinuxakipovew.pdf
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608774a092c0d---wapejunebi.pdf
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/55amf6a225f3o394av8r5otmdt/tugizutan.pdf
    • http://palami.by/images/file/baferuzijusezeji.pdf
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161235982dc848---52859130290.pdf
    • http://x04ydivan.ru/userfiles/file/toxuwavufejibeforik.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_off0000de84.bin
f77240a7d658865417c8a0b0687d9a9bf741dcb42a3b2eb720dfeca67b6d422a
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE84 18648 bytes
font_01_sfnt_off00010e90.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E90 16792 bytes
font_02_sfnt_off000126a7.bin
2a1bbda7e2142cc1c9eceba77c9836311fc9790700e874b100041ce9a486fd0f
pdf-font-stream PDF embedded font (sfnt) at offset 0x126A7 10492 bytes