Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9aab8a1e53173bc…

MALICIOUS

PDF

67.6 KB Created: 2021-09-08 17:17:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 69e9d3be65870786b34440562980cd09 SHA-1: 14d0f8555b809a44ee57b6ba25f8d0d6835c1da1 SHA-256: c9aab8a1e53173bceb1ca274495c0046123b890907f8587fd5853026e331bc07
156 Risk Score

Malware Insights

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

This PDF was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains a link farm pointing to multiple compromised WordPress sites and disposable hosting, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking clear user-facing text but containing embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e734efe49---14838817369.pdf In PDF document text
    • http://dichvubaove.online/upload/files/sewadekonogozul.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/161310ea96f7d1---bikaranibum.pdfIn PDF document text
    • http://yossy.biz/userfiles/file/57495379009.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16137371ed72a2---kiverejolexujafuwajaz.pdfIn PDF document text
    • http://axi-hohenstein.de/userfiles/file/tifuporo.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613752df887d7---fojatilikoledisejegij.pdfIn PDF document text
    • http://www.letnifestiwal.pl/ckfinder/userfiles/files/35865866249.pdfIn PDF document text
    • http://akinmedikal.com/uploads/file/jaxona.pdfIn PDF document text
    • http://gndpta.eu/news_objects/files/rufuvilazok.pdfIn PDF document text
    • http://pi-consulting.ch/download/lagifepedofavidej.pdfIn PDF document text
    • http://isleford.com/filespath/files/20210906172042.pdfIn PDF document text
    • http://biomehl.com/images/content/files/99625288124.pdfIn PDF document text
    • https://smobiil.eu/userfiles/files/dalerofuzatapijekunogofu.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/a80b45e375cf1bbc8f31876ec7a932d5/lavuxavidulapixad.pdfIn PDF document text
    • https://commonwealthsportsawards.com/userfiles/file/vunatamaxodufuraturo.pdfIn PDF document text
    • https://protraderin.com/userfiles/file/rodonubogokujonalejenobum.pdfIn PDF document text
    • https://ruta.hu/ckfinder/userfiles/files/80650919131.pdfIn PDF document text
    • https://ysh.my/userfiles/file/60444052427.pdfIn PDF document text
    • http://geombiagioschettino.eu/userfiles/files/5930620725.pdfIn PDF document text
    • http://osstemcardiotec.com/files/fckeditor/file/8806375566132a9fda2286.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/41919684541.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=deerma+vacuum+cleaner+manualPDF 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_off0000adc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xADC5 14572 bytes
SHA-256: 6685bd548b63791096785237b4819a8749403d726603e6289edf4486c51cd595
font_01_sfnt_off0000d2b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2B6 10080 bytes
SHA-256: f3206d63f2576bc5e3e62dc1f1b64fae7fb46953fa70cca5a7fd8ca14100f6b9
font_02_sfnt_off0000e92a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE92A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1