Malicious PDF — malware analysis report

Static analysis result for SHA-256 a54f3dfb58b55014…

MALICIOUS

PDF

81.4 KB Created: 2021-08-25 04:51:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 17811a0f76e2019feaf94918871d4e8b SHA-1: 8cd3003ff04a3ca3a4c5a9e4583ad4c8bf33824e SHA-256: a54f3dfb58b5501417f96f67ce813642aef6b4ff8869d95652a80c1aa297675a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://pistant.ru/uplcv?utm_term=fourier+series+pdf+free+download
    • https://gkscam.com/userfiles/file/mojos.pdf
    • http://usaoxin.com/userfiles/2021-8/file/72055008699.pdf
    • http://studioarchperissinotto.eu/userfiles/files/18761917849.pdf
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/161114dc34676b---20866966131.pdf
    • https://preprodpcb.com/userfiles/files/namarisowuvavopot.pdf
    • http://z500.si/files/vevavuvefifejulila.pdf
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083e1d99a7f8---23609893986.pdf
    • https://www.truegridpaver.com/wp-content/plugins/super-forms/uploads/php/files/3ca154287c22ae5fc3d24cbde84e4a40/xululiwakujuwigivabox.pdf
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/e8647902405cf856c5842cd255ecd747/sejomazotefufituzix.pdf
    • https://ourcampuswindow.com/ckfinder/userfiles/files/98888020556.pdf
    • http://anatolianlgs.com/userfiles/file/10920873673.pdf
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3b9e306a11---lavujubafomew.pdf
    • http://amoy-art.com/Upload/file/16606914767.pdf
    • http://azseal.net/uploads/userfiles/file/bumibimosove.pdf
    • https://kuepancong.com/contents//files/goxagagarafafudonosawu.pdf
    • http://lpc2529.com/piceditor/file/12830380927.pdf
    • http://clairerolo.com/userfiles/file/doxagugalup.pdf
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e8182f2c5e6---9365865988.pdf
    • http://agiusfuneraldirectors.com/files/file/56415034767.pdf
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/81vtjsoijghd4r15ciugsh381h/75139287055.pdf
    • https://galaxy-training.com/userfiles/file/45291083508.pdf
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1609dabd80b0e0---saxawevipitoves.pdf
    • http://breakevenpoint.pl/uploads/editor/file/91413628236.pdf
    • http://paradisetourkorea.com/FileData/ckfinder/files/20210811_F6C92C82B75AFC2E.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_off0000dac2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAC2 16792 bytes
font_01_sfnt_off0000f2d4.bin
7df2b7aef358a6b1663ecf81e37d74d216855aee02463dcb5f7bbf5c66c4c428
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D4 17004 bytes
font_02_sfnt_off00011ed6.bin
a8a20be919520bca1f099708e0dc8d0d1ae8dcb39543dc27d757e72da541ddc3
pdf-font-stream PDF embedded font (sfnt) at offset 0x11ED6 10556 bytes