Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2754f37ec521372…

MALICIOUS

PDF

76.2 KB Created: 2021-09-30 20:13:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5ff84225cf57a53da16c4a69a7a0d846 SHA-1: 774259f97d618f3d74fe543251d63d0bfef60403 SHA-256: a2754f37ec521372e8d34aa5b6ddc54cfa74669ec09f66c54aaf277e1e0e1879
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm for SEO manipulation or to distribute further malicious content. The ML classifier strongly indicated maliciousness. While no scripts were extracted, the nature of the URLs and the PDF structure point towards a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9939

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://krisoc.ru/uplcv?utm_term=best+minecraft+alt+websites
    • https://presentkompaniet.com/img/content/file/85670561768.pdf
    • http://hyundai-dongdo.vn/images/files/2856915121.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612f36145fc20---raxegezazazokefox.pdf
    • https://tommytest.dish1314.com/data/html_editor/files/93964159225.pdf
    • https://bnbtravels.com/ckfinder/userfiles/files/87733165916.pdf
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/2521326e83c4c31b5c55d3bf91cf6d0c/39878809360.pdf
    • https://ovistar-dz.com/ckfinder/userfiles/files/sazopixeli.pdf
    • https://thingstodobahrain.net/ckfinder/userfiles/files/532663402.pdf
    • https://successalpha.team/upload/files/26689660170.pdf
    • http://www.polni.si/Images/files/94475305652.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/bceca385c4df83ea59a7f13d66d8dc67/64584630588.pdf
    • https://hoanghaie.com/Images_upload/files/8919860254.pdf
    • http://ozdoby-betonowe21.pl/Upload/file/fuliwivosu.pdf
    • http://ityab.com/cache/fck_files/file/musabubenepigunir.pdf
    • https://tlproduct.com/userfiles/file/wojokowotad.pdf
    • http://gabident.pl/local/userfiles/file/lugaweperuxoteb.pdf
    • http://5thaveseniors.org/userfiles/file/kejolebugudibuxunewamewax.pdf
    • http://lifebeachvilla.com/uploads/image/files/xifaremupejavo.pdf
    • http://hairfibers24.com/upload/file/86015613496.pdf
    • https://heatingboiler.ca/fck_upload/file/tebejabesa.pdf
    • https://beyondpins.com/calisma2/files/uploads/ruduwekikeva.pdf
    • http://big-blue-bus.com/pics/fotos/1/file/50693015595.pdf
    • https://soportedevida.mx/ckfinder/userfiles/files/nomaboritirunuvoridi.pdf
    • http://lynhuagiasi.com/Images_upload/files/70407418445.pdf
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/mmo190hbfsh62b2b8422hfsjn6/vuwivisazogenijajet.pdf
    • http://bodybybodyology.com/ckfinder/userfiles/files/nalokeromimowipisade.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c051.bin
46d5c6ff2b1ba6e5ab17938182a63a07341a5fff280e35dbe09c4ddf2f04683e
pdf-font-stream PDF embedded font (sfnt) at offset 0xC051 10656 bytes
font_01_sfnt_off0000d8cc.bin
8f3f7cf99395f840e2e4b3d2aca54807e5edba628983e6c34196eda0a100ab7b
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8CC 18368 bytes
font_02_sfnt_off000108d8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x108D8 16792 bytes