Malicious PDF — malware analysis report

Static analysis result for SHA-256 9fdc11713c6b253e…

MALICIOUS

PDF

78.4 KB Created: 2021-08-28 14:16:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a2b69f86f1153f6a0245bdb9b3ad3d76 SHA-1: 75d5760499fadfbbeb7438672f9aa5db83d224e7 SHA-256: 9fdc11713c6b253ecf04330ad15594a2bd79a88038cc5fe4b93c8649e08c3ba3
196 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 heuristic 'SE_BROWSER_INSTALL_LURE' suggests the document is designed to trick users into installing malicious browser extensions or updates. Numerous URLs extracted from the document, many hosted on compromised CMS upload directories, likely serve as download locations for secondary payloads or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/16110509e24e18---69365096611.pdf In PDF document text
    • https://aprilboya.com/userfiles/file/wemimujexojifori.pdfIn PDF document text
    • http://ekolojikweb.net/upld/userfiles/file/85000735699.pdfIn PDF document text
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16073be22259c0---jibagubemodunuw.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/cec8123ba09ca8d7c24394810091ca57/fumerej.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/lekipubezisabutakuselexe.pdfIn PDF document text
    • https://schmitz.cz/res/file/dekixetegulubapipatakajup.pdfIn PDF document text
    • http://www.deopendeur.org/imgUser/file/79719944105.pdfIn PDF document text
    • https://www.lightingsolutionsal.com/wp-content/plugins/super-forms/uploads/php/files/7bc7bb8c661437ebbde61de4ad85e587/55806532260.pdfIn PDF document text
    • https://www.llgnjinc.com/wp-content/plugins/super-forms/uploads/php/files/0c5d5dc92e1d503dea57ef69c9f1aaf7/tiwosavofir.pdfIn PDF document text
    • https://truck-diagnostic.ru/wp-content/plugins/super-forms/uploads/php/files/aa5de29015c502aaad8280bb062f208c/17773853150.pdfIn PDF document text
    • http://homeopathyhongkong.cn/files/metaloba.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/ruxozenuv.pdfIn PDF document text
    • https://marathonblainville.com/userfiles/files/95081406225.pdfIn PDF document text
    • http://zwickerfoto.hu/_user/file/32862084092.pdfIn PDF document text
    • https://www.jnvhardoi.org/ckfinder/userfiles/files/28785391927.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/nvm18p4n1tlml56cucthjgc2b3/42550314484.pdfIn PDF document text
    • http://bkairconditioner.com/uploads/files/27668123596.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086bee33e9eb---kavok.pdfIn PDF document text
    • http://sirinthepgroup.com/userfiles/file/28026592089.pdfIn PDF document text
    • http://starlightcelebre.com/clients/4/43/43e9139217482d7666ce300faf566241/File/53862377913.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160aea50122acc---29347701600.pdfIn PDF document text
    • http://brette-animation.com/userfiles/file/rupamodisozegirofuxerikip.pdfIn PDF document text
    • http://www.medicellbank.com/userfiles/files/vuwupituxupobobupazo.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/batedixumazulokibe.pdfIn PDF document text
    • http://katyababash.com/images/uploads/file/24995459824.pdfIn PDF document text
    • http://promador.pl/userfiles/file/katabifapupukoxuju.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=attaching+a+pdf+to+an+emailPDF 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_off0000d115.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD115 10780 bytes
SHA-256: 466cc525ef9fc9f1088dd6627d931e8e27877fd20d7ace2f1d6c21dea3a2eb44
font_01_sfnt_off0000e98d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE98D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001019f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1019F 16316 bytes
SHA-256: 5532491943a99585c6626d571f83989851fb769c26fdc1073379378c5d80c0ba