Malicious PDF — malware analysis report

Static analysis result for SHA-256 43921e4a769233a9…

MALICIOUS

PDF

84.3 KB Created: 2021-06-26 14:45:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 28f3be8a5bec15d6a5ebbd927b32aae4 SHA-1: 985944372b9aa5fa4a25b4c50a6f93c5ef31267d SHA-256: 43921e4a769233a9d1a56ded5a8e1b20597d30443b8b7900963e4b2436c49709
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to multiple compromised CMS upload directories, which in turn host other PDF files. The 'SE_INVOICE_LURE' heuristic suggests a phishing or scam intent. While no scripts were directly extracted, the nature of the link farm and the hosting on compromised sites indicates a likely multi-stage attack pattern designed to deliver further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://agenciaboom.com/wp-content/plugins/super-forms/uploads/php/files/8dbtp7vn9igiectn3lhg2vmki1/44869316130.pdf
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/146df7ec0c0c1905b5de8baaea35dd0a/tugesaveguzanem.pdf
    • http://accomplishtheimpossible.com/userfiles_ati/file/nedixulemalulesewanisufi.pdf
    • http://teakdeck.pl/files/file/wubotogid.pdf
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a59b0bb6c8a---49614275596.pdf
    • http://meble-tk.pl/userfiles/file/24933879401.pdf
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/25485434699.pdf
    • http://brenno-tojestto.pl/userfiles/file/72232823470.pdf
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/160778dba0d307---savozanukenipanedevigiz.pdf
    • http://aggengr.com/uploads/CMS/file/21022614186.pdf
    • http://banphimchuot.com/userfiles/file/7270440373.pdf
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afa3fe6a55b---tibofekiligiwiwi.pdf
    • http://sewakendragroup.com/userfiles/file/74108397543.pdf
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0e7fe36bd---penipusikefagofe.pdf
    • http://albino-pitti.com/pub_img/file/wileriwudixegalu.pdf
    • https://stopserv.ru/files/file/xepomevelixugadatefugonan.pdf
    • https://absolut-fit-and-dance.de/wp-content/plugins/super-forms/uploads/php/files/qsgv90btr92e6g4mj9ubv7moke/95202218140.pdf
    • https://ka-base.no/images_content/file/gakitunid.pdf
    • http://shepardfarm.com/clients/877021/File/kipidezitiwe.pdf
    • http://drkoopman.nl/cmsimages/file/62209436229.pdf
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210509011649.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+see+post+of+private+account+on+insta
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/d2f575e0bc9e0dd81c30bc628ae6438a/63341352970.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_off0000e779.bin
21839ff45d409439ddd0dee16e6812f5da3537915360de0a0b437be1cf1a81f2
pdf-font-stream PDF embedded font (sfnt) at offset 0xE779 10668 bytes
font_01_sfnt_off00010021.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10021 16792 bytes
font_02_sfnt_off00011833.bin
6993354dd54e47d1c135ff1e429da872a52c9203e62b1e80db0905b3372c3f0d
pdf-font-stream PDF embedded font (sfnt) at offset 0x11833 16768 bytes