Malicious PDF — malware analysis report

Static analysis result for SHA-256 821b4b19743e15d2…

MALICIOUS

PDF

81.1 KB Created: 2021-06-27 23:58:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 9af9a6d52a28b077ba0b7d2b4a73e1f5 SHA-1: ec6b0b4c8d833750f84865e7e27a4bf927734cb0 SHA-256: 821b4b19743e15d2d10c3cfcb02af3b0e4bb9eae719cebf514f5057494f601f3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains a large number of external links, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document's structure as a link farm suggests an attempt to obscure the ultimate destination and evade initial detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/phhjui17s0k8sv7e0iq8e96652/15596318145.pdf In PDF document text
    • https://www.letspassdriving.co.uk/wp-content/plugins/super-forms/uploads/php/files/e766uf3echjr80rj25eck2b6mp/61659576801.pdfIn PDF document text
    • http://france-ex.com/images/blog//file/89349232627.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/160726c70e6f3a---59803073815.pdfIn PDF document text
    • http://www.rify.us/cms-uploads/files/risobowosapopasiwi.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c11557adb56---61863930377.pdfIn PDF document text
    • http://teakdeck.pl/files/file/83728589673.pdfIn PDF document text
    • http://cdmatik.com/uploads/file/35911238387.pdfIn PDF document text
    • http://china-zub.ru/userfiles/file/41436337754.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/rq9o9adlauten6trv97o4tsa70/85361234349.pdfIn PDF document text
    • https://condicionamentofisico.com/arquivos/file/noporibukupilezasotigik.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160751ca3569c5---60940567259.pdfIn PDF document text
    • https://hgb.se/filer/file/kikuzezamuvasigu.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098f33881121---famasutizukaz.pdfIn PDF document text
    • http://yuanjen.com/ckfinder/userfiles/files/felufujebin.pdfIn PDF document text
    • https://sarujiovalente.com/wp-content/plugins/super-forms/uploads/php/files/vu9klfqfnrshdkknvljg5tfgtb/33099707072.pdfIn PDF document text
    • https://www.chesapeake-lighting.com/wp-content/plugins/super-forms/uploads/php/files/df84fed3b7a55c9d2c8c266c998ab46f/fomixalulanaladupazi.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/16085afc95022d---gibexozojelif.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/822148da205a584adb9bd28b2941c5ba/faxijexavaxodut.pdfIn PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/160c11c84138c1---dazepokofa.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160738ac584521---66203759761.pdfIn PDF document text
    • http://finemetal-cn.com/upload/files/zozadoviwoxateg.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=songs+without+profanityPDF 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_off0000db27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB27 16568 bytes
SHA-256: 8d695699a7324832a5a0aca5dcc8749914b0531fbf9debf9cc364a2f26fb2a61
font_01_sfnt_off00010635.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10635 10832 bytes
SHA-256: 18dad4ac2053fbbd38a9ea406121298dcd9ea9ca12d1b1f4a7b2705decccd4df
font_02_sfnt_off00011f3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F3C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.