Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a82ed0ac9ac5dfe…

MALICIOUS

PDF

81.3 KB Created: 2021-09-24 07:01:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: cdd266618453897af8351e9e18850b13 SHA-1: a27b3141a7c51d5061de372eb505e9668ce83c38 SHA-256: 8a82ed0ac9ac5dfea1c2fa46a1d1d6049f80802147b70f4496447e77fca9031b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to various websites, many of which appear to be compromised or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution through these links. The file's structure as a link farm suggests it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://chcial.ru/uplcv?utm_term=fonts+apk+download PDF link annotation
    • https://akproauto.com/nbloom/fckuploads/file/bapumadupa.pdfIn PDF document text
    • http://arabstina.com/ckfinder/userfiles/files/66944121821.pdfIn PDF document text
    • http://ayurveda-shiatsu-qigong-nice.com/upload/files/gereboselunulevopugusuj.pdfIn PDF document text
    • http://jysfh.com/upload_fck/file/2021-9-7/20210907093519739264.pdfIn PDF document text
    • http://ersenergy.com/UserFiles/file/41807754873.pdfIn PDF document text
    • https://luatsuavina.com/userfiles/file/28269796730.pdfIn PDF document text
    • http://1666-3668.com/attach/userfiles/file/kuzafekisepinanosofif.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/0pee6v7a2pnj9dvit8m7vuumo1/49074757490.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b100db6175---xagerifuxapumibisukozer.pdfIn PDF document text
    • https://pasarant0g3l-turbo-h1t.com/contents/files/36816227307.pdfIn PDF document text
    • http://abnicum.ru/files/file/95692969518.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613aa25f97260---rijonudo.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/161427abe9cb1b---38445171515.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133a9121084b---wuwaviwazowunogelaxenof.pdfIn PDF document text
    • http://abnigakgdsg.friendship-match.com/upload/files/31394741800.pdfIn PDF document text
    • https://leo.tw/upload/ckeditor/files/26630994071.pdfIn PDF document text
    • http://www.lnk-creation.fr/upload/file/32276078031.pdfIn PDF document text
    • http://wixoon.hu/upload/file/36550040544.pdfIn PDF document text
    • http://thietbinuoitom.vn/uploads/userfiles/file/68856897489.pdfIn PDF document text
    • http://soeurs-scjboran.fr/soeurs/upload/files/2280769823.pdfIn PDF document text
    • http://canoeing.by/pics/files/valoxusuju.pdfIn PDF document text
    • http://fvv-hohenfelde.de/sites/default/files/files/6016358843.pdfIn PDF document text
    • http://www.companyforte.com/imagenes/editor/file/1594753752.pdfIn PDF document text
    • http://kibunajcc.com/ckfinder/userfiles/files/felepubejubela.pdfIn PDF document text
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/3153849184.pdfIn PDF document text
    • 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_off0000da4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA4A 10216 bytes
SHA-256: df3ec83f6d69cd1d1193989622be453a8e14713ec6b16d081fc423754347ba42
font_01_sfnt_off0000f165.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF165 18112 bytes
SHA-256: 414be2e6e35ecdef5706737a1832f1370aa0a2928e61a105f7931a41310a7aa2
font_02_sfnt_off00011fb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FB3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1