Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cf4f57bb5705262…

MALICIOUS

PDF

78.0 KB Created: 2021-09-16 05:06:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e3325d8586409abf065de0707c4b4950 SHA-1: 390096755d41a91b89751cfe35fcd0ac31b9a2e4 SHA-256: 1cf4f57bb570526215eaf32bfb89e31cbb12df996b467c4b6fc45d9e33d3ab47
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as containing a link farm and was classified as malicious by an ML model and ClamAV. The heuristics indicate that the PDF points to compromised CMS upload storage and uses disposable hosting, suggesting a phishing or malware distribution attempt. The embedded URLs, while some are marked benign, contribute to the overall pattern of directing users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://matonaklawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/44420245804.pdf In PDF document text
    • http://portaldeaquidauana.com.br/ckfinder/userfiles/files/34206481782.pdfIn PDF document text
    • http://www.facyt.com.ar/ckfinder/userfiles/files/98491029073.pdfIn PDF document text
    • https://apatity.verlauf-ekb.ru/admin/ckfinder/userfiles/files/rewumatinuzukit.pdfIn PDF document text
    • https://szallas-karpatalja.net/upload/nalixugopotokexakowipope.pdfIn PDF document text
    • http://bielwod.com/userfiles/file/50554310057.pdfIn PDF document text
    • http://xn--pr3b03lcdvwu9dpynqkc.com/DATA/file/20210902041925.pdfIn PDF document text
    • http://www.euro-fly.eu/userfiles/files/rinebalonijilakorelofu.pdfIn PDF document text
    • https://dichvuketoansg.com/luutru/files/83062044108.pdfIn PDF document text
    • http://cameranichietsu.com/luutru/files/78328762829.pdfIn PDF document text
    • https://vico-real-estate.com/ckfinder/userfiles/files/16371127600.pdfIn PDF document text
    • http://brilspa.ro/userfiles/file///15147121665.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/161323f1f7e8a2---mitalelanafava.pdfIn PDF document text
    • https://indicaperu.com/userfiles/file/pelulisigexogenipoze.pdfIn PDF document text
    • https://sssmri.com/ckfinder/userfiles/files/bezewukikep.pdfIn PDF document text
    • http://evohome.pl/userfiles/file/84175340220.pdfIn PDF document text
    • http://sino-web.net/filespath/files/20210901224913.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1613de11e23d70---xavovetap.pdfIn PDF document text
    • https://mehreganimaging.ir/images/upload/files/25328250827.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/a1a5528cf054cc26aa36209a98c8ad5f/xidasifaragavakozurojoged.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/07541d653fb7ae55ebe2f70e52a739ce/48012983233.pdfIn PDF document text
    • http://filtrydokoparek.pl/img/all/80782730030.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=gb+insta+download+for+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_off0000ce2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE2D 10480 bytes
SHA-256: be46636e89a4433f54fb76bdc08482b9e91a3bb7a72870e15405bfac1e067ec0
font_01_sfnt_off0000e626.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE626 16984 bytes
SHA-256: d8f38663873a1b729c1d10217b2b6d0973757e98eb7e884a5281ce5ccf551ff8
font_02_sfnt_off00011215.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11215 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1