Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3858a15ba9823ac…

MALICIOUS

PDF

86.9 KB Created: 2021-07-06 03:36:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: ce1b16f14ff2b32699f2f808e1d011e8 SHA-1: 8ebfa569c57c30e91758f9b1bda933ec1e661322 SHA-256: e3858a15ba9823ac8748a56b9cc8a830b87cc76e250881de59ec00a624794e09
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the structure and URL patterns suggest an attempt to direct users to potentially harmful content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3071513d1---180712476.pdf In PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082808f9f169---fogujewazibabapodipawawa.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/7rq32hclhs12v9su3eq0geo83a/vevinadeduvavexaxe.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/d2dbbc366a843f82d25d457e1c866e53/jopowufizetow.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607542704c43f---86161720145.pdfIn PDF document text
    • http://amctop.com/board_data/editor_img/file/202105100453.pdfIn PDF document text
    • https://x-software.cz/data/file/10027055272.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/c69c47d74b0813e4ea3463d4452bc347/59550862973.pdfIn PDF document text
    • https://www.basur-tedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c149183471---kaxis.pdfIn PDF document text
    • http://cokhiminhhien.com/media/ftp/file/gukenarizefakimunu.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/eld7or3epgio4qh4n5id61qs7s/wizezelapagapefezeji.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608062a960faa---83733993643.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/57617750834.pdfIn PDF document text
    • https://noihoithanhtuan.com/media/ftp/file/47976893660.pdfIn PDF document text
    • http://aptchasers.com/FCKeditor/userfiles/file/mowovixalaxomurifotam.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/tlvgtaahcidgejg85fi090a0hs/45718162752.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160cee7022abcc---kagezejemimo.pdfIn PDF document text
    • https://szaniterplaza.hu/ckfinder/userfiles/files/38578174310.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607f110a6691d---mewud.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7fc8cf18a1---52798592497.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/782fc5f910070259533563cbe577f407/64623378740.pdfIn PDF document text
    • http://www.peretprod.ro/content-images/file/wejavigadolumexaf.pdfIn PDF document text
    • https://mvmdigital.gr/files/files/xerivubojaviwigovadil.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160874a0291b1e---vajipijuniduxo.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aacf8dac31c---bowizolepulelun.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/2ab926a1ae07841ae89be1ca76e1c572/timomeritubezopineba.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1608683c73b8a9---2698702516.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=scrooge+cold+quotesPDF 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_off0000f154.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF154 10508 bytes
SHA-256: b4aef395ba4b0e080eb63c42a004b696dc45c7dcf102543ee43053836919bf19
font_01_sfnt_off000108d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108D5 17000 bytes
SHA-256: 170c362cc7b0e32a7d0cdec2a53f2d9a2c5fb98cff38b30bd5531764df1ef061
font_02_sfnt_off00013486.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13486 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1