Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae3e5b5b9299e0fb…

MALICIOUS

PDF

84.8 KB Created: 2021-09-01 10:30:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 6678c4efbf0d71253ff8acdc6a2d04c8 SHA-1: 1e90c4bd792a07b33a83d76fbddbeb33fb4474c9 SHA-256: ae3e5b5b9299e0fbad114e588d20785b8f60f1e5abe67d65c3eed23ff9ea68b7
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of external links, many of which point to compromised WordPress sites or disposable hosting. The ML classifier strongly indicated maliciousness. The primary attack pattern observed is the use of a link farm to direct users to potentially malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • 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://wastran.ru/uplcv?utm_term=gcd+of+three+numbers+in+java PDF link annotation
    • http://absolutelyneon.com/userfiles/file/99286978032.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/b3012ca680bb3178245800ba0deb64a6/firarodifapaxilugozegalab.pdfIn PDF document text
    • http://rustproofingottawa.com/userfiles/file/33743512096.pdfIn PDF document text
    • https://agermag.ro/mm/file/41700136672.pdfIn PDF document text
    • http://cybernet.asia/UserFiles/File/35463918141.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/d9caf09417af28a4f4145f93fea555ad/jigasekinofovakatepijived.pdfIn PDF document text
    • http://laros.cz/UserFiles/file/12846799337.pdfIn PDF document text
    • http://taskentcompany.com/userfiles/file/26402636005.pdfIn PDF document text
    • http://tea-ra.com/user_data/upload/save_image/files/legolesuzidajamipejixil.pdfIn PDF document text
    • https://www.bocamvigliesrooms.com/wp-content/plugins/super-forms/uploads/php/files/b7973ae789ee8181a52a612dadca4d3d/16949342390.pdfIn PDF document text
    • https://widerbet.pl/userfiles/file/talewogowofimalamana.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/7cfe59c6e050e221b6fb5ad572f6f6a4/gasiwas.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1609d59b582e56---68827745761.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077634f1f4f3---31737368665.pdfIn PDF document text
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/mrmhipg3fmqdr6tv6gslfobmaa/8394033173.pdfIn PDF document text
    • https://chingchia.com/uploads/files/202108201522025981.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160b659ceed482---66134790863.pdfIn PDF document text
    • http://www.anglometais.com.br/adm/Editor/ckfinder/userfiles/files/nibani.pdfIn PDF document text
    • http://amdind.com/userfiles/file/76006469528.pdfIn PDF document text
    • http://ddaengshop.com/ckupload/files/30804741749.pdfIn PDF document text
    • http://makassitools.com/userfiles/file///gefagatadasomebosodinun.pdfIn PDF document text
    • https://digireg.cn/upload/2616075889.pdfIn PDF document text
    • https://dla-pracownika.pl/pliki_user/File/98310420436.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d4a48d8ee2---tulewotuges.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_off0000e160.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE160 19244 bytes
SHA-256: 41de6fa0bd880b221c56cd76d8adc56aa742a913b911913492548a65eb51d27f
font_01_sfnt_off0001131d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1131D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012b34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B34 11172 bytes
SHA-256: 55e1ee775b4dfdf90495ff1d2b89ed2042852c6ccbc5eb52f4334d7d0057751f