Malicious PDF — malware analysis report

Static analysis result for SHA-256 1001ab992ce9cd11…

MALICIOUS

PDF

86.1 KB Created: 2021-08-25 09:55:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c17ec16dea9b0d721cdd0dd70761e8e1 SHA-1: dd02ab4e5b7a8d1014b17facd0a2c2f954a23c0b SHA-256: 1001ab992ce9cd11d0868df166fb3f989223f0edd0859ef5d435a66529227026
96 Risk Score

Malware Insights

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

This PDF file contains numerous embedded URLs that point to compromised WordPress sites and other disposable hosting. The heuristic firings indicate it functions as a link farm, likely intended to redirect users to malicious content or phishing pages. The ML classifier strongly supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://inwebjor.ru/uplcv?utm_term=secondary+math+module+1+sequences+1.3+answers
    • https://premium-house.uz/images/file/40239085782.pdf
    • http://turatabor.hu/media/58707557235.pdf
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/4d84384932c7aa9a43e82a33c18fdb49/75520837190.pdf
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/b9d57545fad1693b0b483ea9755adbe4/18287085386.pdf
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/pat2qd37mah4n4j33gfb1gpbqh/43443352576.pdf
    • http://lycee-elm.org/userfiles/file/68990677012.pdf
    • http://open.ua/uploads/ckeditor/files/koguvibado.pdf
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160bcf18a2c99e---70623960040.pdf
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/defdd758de1d8fb60c3789880c86495e/67248435507.pdf
    • https://pfollowers.com/ci/userfiles/files/56644470892.pdf
    • http://4yoga.by/pics/files/69640728160.pdf
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/1608469e675fd3---wiluziturisufuki.pdf
    • http://studioaba.net/userfiles/files/14384611897.pdf
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090475cdf589---69780798383.pdf
    • http://rund.cz/UserFiles/File/99393504745.pdf
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160e8cff98b3de---togom.pdf
    • https://comobrew.com/newsite/images/user_uploads/file/poxivifipikot.pdf
    • https://confetti-seasons.ru/upload/files/dowupogasukabifuzigarepi.pdf
    • https://cbdc.co/uploads/ckfinder/userfiles/files/76293313253.pdf
    • http://dobrejaja.com/Upload/file/83062698872.pdf
    • http://bursaceyizgelinlik.com/images_upload/files/80626661002.pdf
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/ae6sbpeofp3l1cj3ifu06gqf8d/zajevefawozutivowiz.pdf
    • http://cck-brno.cz/ckfinder/userfiles/files/diduzimezujilikuvum.pdf
    • http://fabtur.ru/upload/files/ribupipumexutejete.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16070a98c351d1---54411921985.pdf
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/4bbb9bdb73b458ed449e2acd38664bbf/75465888975.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_off0000e9ea.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9EA 16792 bytes
font_01_sfnt_off000101fc.bin
83cb4e713ba05d86f2e5971b85411dcd892f0df0d9ac2115e366a2f4269e3f46
pdf-font-stream PDF embedded font (sfnt) at offset 0x101FC 17208 bytes
font_02_sfnt_off00012e89.bin
e1b075043842d1f59dc34bb1d0e15356a78a710949feae7f57e962daa13907db
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E89 11356 bytes