Malicious PDF — malware analysis report

Static analysis result for SHA-256 53cb47693399d46b…

MALICIOUS

PDF

87.4 KB Created: 2021-09-03 16:04:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e5999f5ba35514163869144d68982f81 SHA-1: ea53907ca66001e4cd691b2dfca7894a885efad2 SHA-256: 53cb47693399d46b46ed345e84741fc26704957f007bf03b38d574054537a710
156 Risk Score

Malware Insights

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

The PDF contains multiple embedded URLs that form a link farm, a common technique for phishing or distributing malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the URLs are hosted on disposable or compromised domains, further supporting a phishing or malware distribution scenario.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://gtlmarinefuel.com/userfiles/file/nuzoxumatuxuzujedufepajug.pdf In PDF document text
    • https://etre-cheval.fr/Applications/MAMP/htdocs/etre%20cheval/news_pix/file/malitufapebujimoladoxu.pdfIn PDF document text
    • http://alianzablue.com/aym_image/files/80456530950.pdfIn PDF document text
    • http://aire-limpio.com/img/editor/file/4425711702.pdfIn PDF document text
    • http://www.sas.edu.mn/ckfinder/userfiles/files/pulirasepuxiwumarowakupub.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/wazasafakabexuba.pdfIn PDF document text
    • http://ponyomaru.com/files/files/52857424829.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/3771452061.pdfIn PDF document text
    • http://www.oneworldkarate.com/fckeditorimages/userfiles/file/52526239488.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/satatebudizelu.pdfIn PDF document text
    • http://medicapoland.pl/uploaded/file/29027311194.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160745b37da051---bakenagefivevolugamoxab.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/mph4uh577vl4e98tuhl8qofgc1/14038694914.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/bae641c22fb82adae5d328aae26c89f2/27118668988.pdfIn PDF document text
    • http://noahmission.org/dataroom/file/73883009002.pdfIn PDF document text
    • http://fincasotilloviejo.es/files/sotillo/_repo/file/19182820538.pdfIn PDF document text
    • https://gyandeepjkss.org/userfiles/file/84696890018.pdfIn PDF document text
    • http://tv-sat.cz/userfiles/file/badobejupevo.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f46f6afe76---49985808781.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082daaec74e6---gafumi.pdfIn PDF document text
    • http://sieuthihatgiong.vn/webroot/img/files/gajukakixibedotojufigeve.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/bca4b5281e547cb5f29cda979d50ab95/7227536809.pdfIn PDF document text
    • https://malashealthcare.com/userfiles/files/nubolivifusowoj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=types+of+audio+amplifiers+pdfPDF 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_off0000f20d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF20D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010a24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A24 10636 bytes
SHA-256: cd787b805202795b768a9a6b6f6f2203260ab2af3d1ff3d13abd5d1f80cc8a7a
font_02_sfnt_off00012276.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12276 17468 bytes
SHA-256: 04fa16b1b958da44865ce40a7653fc446f4912f20fca88b95ba31bcfe979219b