Malicious PDF — malware analysis report

Static analysis result for SHA-256 22a4417bdfcd48e4…

MALICIOUS

PDF

75.7 KB Created: 2021-09-13 01:09:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 277f758d49a37a159230972fb1974d7d SHA-1: 5700723e50d1aecc706e13d892e07c44787f52d4 SHA-256: 22a4417bdfcd48e4fafb07227bf983709d388c00a12691ce1c04281fde9b6535
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous other PDF files hosted on various domains, many of which are associated with compromised CMS uploads. This structure suggests an attempt to distribute malicious content or phish for information by luring users to click on these links. The ML classifier strongly supports the malicious verdict.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://miltonmattox.com/userfiles/file/99212223118.pdf In PDF document text
    • http://ventensis.lt/public/ckfinder/userfiles/files/41098770127.pdfIn PDF document text
    • http://ericshartman.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zogagorinufagopogunuxa.pdfIn PDF document text
    • http://phuvuongcorp.com/luutru/files/gitejuwotizusapo.pdfIn PDF document text
    • http://rent-lease-no1.com/userfiles/file/20210904165021.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/pger8mu8b1uc570udc9mkkr1je/vaxawegujimeguniguzitubof.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613005ebd1847---xogako.pdfIn PDF document text
    • http://martonaroniskola.net/userfiles/file/39741428782.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/19777248124.pdfIn PDF document text
    • http://dywin.com/uploadfile/files/pidetepofutamamunelugigo.pdfIn PDF document text
    • https://vialivonica.eu/userfiles/files/bonibisefajilogu.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1612f4f955b603---lezes.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/81212744724.pdfIn PDF document text
    • http://teewer.mn/ckfinder/userfiles/files/finelisafedetaxutovozamo.pdfIn PDF document text
    • http://self119.net/upload/userfiles/2021/09/files/210903130505.pdfIn PDF document text
    • https://kccegis.com/upfiles/content/file/20210912044835.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/gfbis182s5lbqlc8db28l0mt53/8702117112.pdfIn PDF document text
    • http://privateeducation.sg/verzsape/demo/upload/admin/files/jinupexowesul.pdfIn PDF document text
    • https://vgi-vn.vn/app/webroot/img/files/ninowebobenoxevojulokuro.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613a4a22caa37---19662356809.pdfIn PDF document text
    • https://www.champagne-auge-dascier.com/ckfinder/userfiles/files/kupaxixalusobonivorub.pdfIn PDF document text
    • http://hanaelectric.com/userData/board/file/87789190583.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/664d15ef6d2f4d21ff659556fd954451/97295527764.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=chhota+bheem+race+game+mod+apkPDF 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_off0000c351.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC351 17520 bytes
SHA-256: c479dfbbcb068c14b50b1f91b2c9528fb11cb5f9b30fdd449419ee138c203ae4
font_01_sfnt_off0000f0e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E8 10816 bytes
SHA-256: bb19ca2b908a790d3a0d7a0f37f81e4d5f0ea82ee8ec8f5b0802e398889b0b84
font_02_sfnt_off0001097a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1097A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1