Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9fe29f435d56de8…

MALICIOUS

PDF

81.6 KB Created: 2021-09-04 22:46:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 613b5d82dcbc3c42d5058c55cbfa3ac8 SHA-1: cdc1f70f777cacd0492285c0bed110a1714fd693 SHA-256: c9fe29f435d56de8eb72a8cd30ed319a428f850dc9e1abb835bed97e3f41367f
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple potentially compromised or disposable hosting sites, which is a common tactic for phishing or malware distribution. No scripts were extracted, but the presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest the document's purpose is to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9f4ed711cd415067ec9045d8b44b9baf/buxiva.pdf In PDF document text
    • http://furniture83.com/upload/files/firebaxatab.pdfIn PDF document text
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/73b781224f3fb40c9041512e7bd16fc2/15509866358.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/e73hpk77tl2nkq1tgfrvdj8685/kivefozomiredinurawube.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160948dcd58136---miluvilegofarawanumava.pdfIn PDF document text
    • http://robbinsfamilyhealthcare.com/clients/2/2c/2c787fa606fc56c3a3a24dfc5409695f/File/51657232773.pdfIn PDF document text
    • http://goksirkrupskimlyn.pl/img/upload/files/viloxuvilo.pdfIn PDF document text
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d1ecf2ccbe---42098756695.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/96266408382.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160816fdfca770---20730308999.pdfIn PDF document text
    • https://majorsagilekvaros.hu/uploads/file/mewubosefeturonopota.pdfIn PDF document text
    • http://ztkammer.at/uploads/file/xowefuxazuwasanibopeweni.pdfIn PDF document text
    • http://xn----7sbakif2a3azdub.xn--p1ai/admin/ckfinder/userfiles/files/80901725790.pdfIn PDF document text
    • https://pnlcoach.com/misc2/file/In PDF document text
    • http://4x4autok.hu/userfiles/files/tefawovawuviruwigogep.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file///42167151517.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=osteomyelitis+treatment+pdfPDF 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_off0000db54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB54 10796 bytes
SHA-256: 4c36c20e645b35be36af39c0e1a2f44f63fae5fa74aab83fa4550340f1e2e875
font_01_sfnt_off0000f432.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF432 17540 bytes
SHA-256: 0a53c7edc6821cef35cb4dfbf17279ea1336742838f3d05d14409c1fee43b3c5
font_02_sfnt_off000121a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1