Malicious PDF — malware analysis report

Static analysis result for SHA-256 81a2bcaf8ce631b2…

MALICIOUS

PDF

85.0 KB Created: 2021-09-23 10:14:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 0d235380db295db9a03ae12d52fe9558 SHA-1: bbcf63674c4a60b2f21ca557c5bc39566049c1c9 SHA-256: 81a2bcaf8ce631b27b066f3f3267f352aa8a4394b550aa4467fa0b2009d6fe94
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV detection as a phishing/trojan. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates the document is part of a link farm hosted on disposable domains, suggesting a phishing or malware distribution campaign. The numerous embedded URLs point to a network of sites, likely intended to host malicious content or redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://tubesealer.com/uploaded/file/851137986612e987aefaec.pdf In PDF document text
    • http://isisthailand.org/file_media/file_image/file/59778304725.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/9192169947.pdfIn PDF document text
    • http://cbcom.fr/ressource/site-image/files/dejasupa.pdfIn PDF document text
    • https://kisikana.hr/UserFiles/files/64459631856.pdfIn PDF document text
    • http://kemenyseprosiklos.hu/upload/file/61970325882.pdfIn PDF document text
    • http://svatba-emi.com/uploads/pages/files/zatolamidegawumi.pdfIn PDF document text
    • http://nemeckystrakac.sk/editor_uploads/files/pikef.pdfIn PDF document text
    • http://staceyasp.com/UserFiles/file/32716209177.pdfIn PDF document text
    • https://nomaquito-travel.com/editor-images/95527775073.pdfIn PDF document text
    • http://arniuniversity.in/ci/userfiles/files/simorusejebalukizogisuvux.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/nexovu.pdfIn PDF document text
    • http://a2kat.ru/userfiles/file/tosapifinugugo.pdfIn PDF document text
    • https://embassyinvietnam.com/webroot/img/files/wejiki.pdfIn PDF document text
    • http://net-marketing.hu/images/files/47539857097.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/92865797262.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/kaxevugoru.pdfIn PDF document text
    • https://inprovitchile.com/ckfinder/userfiles/files/faxafojis.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/ltqtcb0ff2aorrk7gr626uaub0/41415717232.pdfIn PDF document text
    • https://doctmcooper.com/userfiles/files/88337299568.pdfIn PDF document text
    • http://greentreeprep.com/cote_dor_import/admin/ckfinder/userfiles/files/mawazizedegonosub.pdfIn PDF document text
    • https://rjpexport.com/files/ravawodekupug.pdfIn PDF document text
    • http://0932018255.kad.tw/kads/ckfinder/userfiles/files/nakaf.pdfIn PDF document text
    • https://didacostruzioni.it/userfiles/file/77854265633.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c17ca43dc2---bexojexuwipifidi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=cara+menjalankan+file+exe+di+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_off0000e832.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE832 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010044.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10044 17612 bytes
SHA-256: d4aa0c26854d911c664801b0dcb612222cd9be44c5c1beed321b58fb12b3f304
font_02_sfnt_off00012dc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DC9 10604 bytes
SHA-256: 84e6c3609b7f1bbeffa4ce780416f7f630d683f04b81a53af0163e060eabef83