Malicious PDF — malware analysis report

Static analysis result for SHA-256 a23e011cf3e2e0e1…

MALICIOUS

PDF

82.3 KB Created: 2021-09-09 19:47:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 0efd6fe043552850cd8ddd987479cf52 SHA-1: 1c3f9c2f9a8c39489fc08de9db16be213fe8b652 SHA-256: a23e011cf3e2e0e100f20b66227d38c030e8c825ea0b33fe5feb49e5ee103198
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. The sample also exhibits characteristics of a link farm, with numerous URLs pointing to external resources, some of which are hosted on compromised WordPress sites. This suggests the PDF is designed to redirect users to malicious sites, likely for phishing or to download further malware, aligning with the ClamAV detection of Pdf.Phishing.Trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://garageanything.com/js/upload/files/38231107464.pdf In PDF document text
    • http://yokosohk.com/files/fckfiles/file/noxideterogadusevuse.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210909061732_562389841.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16139d3932ccc1---lurevimubutugopoxe.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1613550ebed5a3---nitijawaxij.pdfIn PDF document text
    • https://thanaclusterwestgate.leaddeehub.com/userfiles/files/3069000812.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/57541787013.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f05c064191---12495521363.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/096a4e54c64cf07cf338d524fd121faa/dapevuxutanizulimala.pdfIn PDF document text
    • http://rana-international.com/userfiles/files/muvonilu.pdfIn PDF document text
    • http://indianspringhomes.com/userfiles/files/ribevu.pdfIn PDF document text
    • http://atomleasing.ru/media/File/76637290476.pdfIn PDF document text
    • http://89928386.com/uploads/files/202109012321562863.pdfIn PDF document text
    • http://xinchenfast.com/upload/file/74098005941.pdfIn PDF document text
    • http://machulski.com/public/file/dowaserimerer.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132810e32b29---kanesifexajan.pdfIn PDF document text
    • http://nelly-design.ru/upload/files/zireniroxibajapijenotez.pdfIn PDF document text
    • http://mvpbuilding.com/userfiles/file/fipipofavuze.pdfIn PDF document text
    • https://ccskin.com/geektic/files/jabewode.pdfIn PDF document text
    • http://fishtech.org/uploads/userfiles/file/file/pizojubosur.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135c69dd5799---kenemifeviwipoxunirito.pdfIn PDF document text
    • http://neonatal-surgery.ru/userfiles/files/80257269162.pdfIn PDF document text
    • http://honderhotel.com/UploadFiles/FCKeditor/20210906073417.pdfIn PDF document text
    • https://profix.fr/ckfinder/userfiles/files/3211224739.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+use+laptop+mouse+and+keyboard+on+androidPDF 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_off0000da18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f22a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF22A 18516 bytes
SHA-256: f4de3e358882aa94cc8a15d7ab5d1f127e039ccc4aa80421bda5d90159c3ccc0
font_02_sfnt_off000121ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121EE 11076 bytes
SHA-256: 448a367eee636c1d4a7c45a747b5b87cfd896f519ed506b6ccff4c8649993edf