Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac56e9b5b8d2cffa…

MALICIOUS

PDF

79.4 KB Created: 2021-09-12 21:08:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a2e08eab97fc2fa83c08055d8a4b93cb SHA-1: 9167b3a076c9b4b10703537a84c1c9b1864de62d SHA-256: ac56e9b5b8d2cffa34d2c7decc4c843418e6ebbe77bc637b67503e7852528477
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/e6e76c72eef4174f8a4caad6acdf42cc/34069890620.pdf In PDF document text
    • http://3dsami.org/uploadfilefiles/28991970338.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f902e38fcb---26203149165.pdfIn PDF document text
    • https://www.frontieregypt.com/sites/all/libraries/ckfinder/userfiles/files/xezux.pdfIn PDF document text
    • http://kodemari.info/data/files/gudozor.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612f71c3c212f---11902537386.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136bc0adb91e---seweferijalesokafoz.pdfIn PDF document text
    • https://arbormaster.net/uploads/files/90204009668.pdfIn PDF document text
    • https://atpl.aero/ckfinder/userfiles/files/74416195083.pdfIn PDF document text
    • https://jungleflightchiangmai.jungle-flight.com/Uploads/files/gufikotezelolajat.pdfIn PDF document text
    • http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/tenolupup.pdfIn PDF document text
    • http://emannsltd.com/userfiles/70488432106.pdfIn PDF document text
    • https://moolans.com/uploads/files/96071763116.pdfIn PDF document text
    • https://brtim.com/uploads/wysiwyg/files/88217555536.pdfIn PDF document text
    • https://happen.webasl.com/userfiles/file/12901725726.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1612f29f30f634---duwesepenejan.pdfIn PDF document text
    • http://teleserviciomalaga.com/ckfinder/userfiles/files/60655797318.pdfIn PDF document text
    • http://marinda.ru/pics/images/file/dalonumigixizo.pdfIn PDF document text
    • http://physio-praxismitte.de/userfiles/tifofolakixunirekenikava.pdfIn PDF document text
    • http://domosplast.hu/files/file/rerarutolaleset.pdfIn PDF document text
    • http://liily.jp/upload/file/20210906200612.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=sebuah+seni+bersikap+bodo+amat+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_off0000d18a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD18A 16732 bytes
SHA-256: 48cd76964c2be19f04467c7b248416858d6467730e946cca40e770a7ac0bd6ff
font_01_sfnt_off0000fd3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD3B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011552.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11552 11124 bytes
SHA-256: a802054eaefb7a18f893d261b4fb6313c6ea0ca27a72aa1f21bea940741daa67