Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ad8f26ddfdcceff…

MALICIOUS

PDF

75.9 KB Created: 2021-06-20 10:41:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ccdd425f524372425ea2367d37946c05 SHA-1: 24e8993e6814c6cf724c65f365b8914570a0f784 SHA-256: 5ad8f26ddfdcceffbce0fca3754fefbdd433ec8688bf8a19201d3d4214aad592
164 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to compromised websites and other PDF files, likely for SEO manipulation or to host phishing content. The presence of multiple compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://nexxosrealty.com/userfiles/files/fewid.pdf
    • http://sillajen.com/fckeditor/_upload/file/13508583848.pdf
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607acc91764a4---kavukudavogobirop.pdf
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/n91co2at2rd21h430ufl99r3nh/49920957031.pdf
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d901a75d25b90168c7a4a94c52ca8957/gebivixetes.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160920a1c13930---xeliwogirogolexobipa.pdf
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/250ln0uu0a2aink0vu5dmp5poh/83983663933.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a04f6168570---67605507929.pdf
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/bduvbqu98upd2kvf82milocvom/14035928059.pdf
    • http://aiswaryamatrimonials.com/fck_uploads/file/lujevizesotogin.pdf
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/8176dvrein0fkfevo80tsvefa7/zokonimowoserup.pdf
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/3d984c32260bd947fff283629cec1901/22310490253.pdf
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607c09e7add51---26712239955.pdf
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/0njbju5jdvn0drn0sh43tcgill/diwex.pdf
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/b04723c6f2464aa404faf78f80b8359b/begudenugafofedufifa.pdf
    • http://fedorahosted.org/lohit
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=9th+new+syllabus+social+science+guide
    • 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://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0000deb1.bin
ce9b83163a7672d08ac5b3b6dc051fed939b6c309def183069af690e3f4f242e
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xDEB1 11352 bytes
font_00_sfnt_off0000cbf0.bin
ca2ff4c15f2b0c83be1bd9a89df9cc620efdecf954a8eb97424861b1504e4105
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBF0 5500 bytes
font_02_sfnt_off0000fb62.bin
b65516ee308ab446d90479ef3541800c43b83b03c6876dcb6ed0fe4cf7cae88d
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB62 10884 bytes