Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5d8151eaec4cb9a…

MALICIOUS

PDF

85.0 KB Created: 2021-07-12 16:59:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4cfdc833408df0c83b3eb53e2a91a643 SHA-1: c318a43b735a669d546dccee7c2b838785acc308 SHA-256: e5d8151eaec4cb9aafc17cb74bd6ffa407fce4dbf951865de639fa60c98de2aa
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous URLs pointing to compromised CMS upload directories. The primary purpose appears to be SEO manipulation or directing users to potentially malicious content hosted on these compromised sites. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific user-facing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ec436aa60ed---mewawosokes.pdf
    • http://niengrangchuyensau.com/upload/contentFile/file/29963665982.pdf
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/70c05f48d98a665300909fd67177f21c/vanevijotepotutomarojawo.pdf
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/e0355771d1ffe72c608bd8450f4c733b/56038300359.pdf
    • http://nacnsuaa.com/clients/4/49/49ab1acc6c62b5a39110d621a19f71c0/File/fikitomabutukemo.pdf
    • http://bpsstudio.hu/uploads/19261368278.pdf
    • http://escqatar.com/uploads/userfiles/file/file/94275889779.pdf
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/t6173p9neh68siagvlabcc5d66/bifadodepitimopanawavap.pdf
    • https://airtelco.com/data/users/_/email/files/99565587696.pdf
    • http://aozbt.com/clients/3/33/335f642cf73e2ad82edc7dd4a76dad4e/File/pifovabotibowimo.pdf
    • http://zonazero.es/userfiles/file/2693059952.pdf
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/dmjp7d7e8tflfolsl2svse0534/rupigelikidujejefodedif.pdf
    • https://angkorphotographyguide.com/userfiles/file/dudeziwizuragolewuwe.pdf
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ec3faf161f9---18556960175.pdf
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/c3c8462f1d43ec826b42fd5926654dea/bulalirisabuxowamigoleg.pdf
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c5a7edc0ec---rebaxifaja.pdf
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160838475a0cec---15968604205.pdf
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608840bd68495---narafidujanavazidiwi.pdf
    • http://whewfamily.com/clients/12004/File/14812501115.pdf
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/160bab2313105c---jamifamovuvojugoxege.pdf
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160958b21354a3---nedakexawixom.pdf
    • http://svenstavik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160851fe982d6b---repakamavigixoki.pdf
    • http://www.yoko-ono.be/images/userfiles/file/71119506492.pdf
    • http://umrllc.com/userfiles/files/3030951614.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=find+the+square+root+of+144+by+repeated+subtraction+method
    • 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_off0000e846.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE846 16792 bytes
font_01_sfnt_off0001005d.bin
acd3a76a481466d669b33970fb2a09d7d8d4ce967143f06475eebae973524dd6
pdf-font-stream PDF embedded font (sfnt) at offset 0x1005D 11444 bytes
font_02_sfnt_off00011ade.bin
d7a12c508c3faa70a0238c19f3389ce1657dc48d21ec64b9ad6f22bef793ac9f
pdf-font-stream PDF embedded font (sfnt) at offset 0x11ADE 16948 bytes