Malicious PDF — malware analysis report

Static analysis result for SHA-256 7955473d420cd667…

MALICIOUS

PDF

100.5 KB Created: 2021-09-15 21:04:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 88ed18c0d9e54275798f78c9a1d487c1 SHA-1: 7b245b04eebe1e1d1b7160d445ca928853f2586f SHA-256: 7955473d420cd6675754fbded753e9e187aae50f56b995e3b4c5e1583518396c
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm for SEO manipulation or to host further malicious content. The ML classifier strongly flagged this PDF as malicious, and the presence of multiple external URIs supports a malicious intent. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://catamma.ru/uplcv?utm_term=sword+art+online+alicization+season+2+episode+7 PDF link annotation
    • http://tumwebthailand.com/ckfinder/userfiles/files/25755469921.pdfIn PDF document text
    • http://kamennykoberec.eu/editor_uploads/system/files/jagagixakuzazemadusig.pdfIn PDF document text
    • https://magicdiscoradio.hu/userfiles/file/nusosetanudawokox.pdfIn PDF document text
    • https://vibanghanoi.com/uploads/files/wuwim.pdfIn PDF document text
    • https://taevlingar.se/images/pages/file/33298545950.pdfIn PDF document text
    • http://magyaringatlanadatbazis.hu/dev/_user/file/ragibububufigenaku.pdfIn PDF document text
    • https://ecodiagnost.com/ckfinder/userfiles/files/muwuvaragipew.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a5eed91e07---fatanexevogubupofozimij.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a620ca1e29---56941885798.pdfIn PDF document text
    • http://saothienemb.com/uploads/images/files/taxare.pdfIn PDF document text
    • https://durgabas.coop.np/ckfinder/userfiles/files/mobuzupow.pdfIn PDF document text
    • https://dimensioninteractive.com/WYSIWYGImage/file/10102396650.pdfIn PDF document text
    • https://fishuntpesca.it/file/48011768462.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ca6d292c8c---51772042992.pdfIn PDF document text
    • http://thermcom.cz/userfiles/file/31034010089.pdfIn PDF document text
    • https://durgabas.coop.np/ckfinder/userfiles/files/tuwokakimogowugap.pdfIn PDF document text
    • http://astorandblack.net/emailer/userfiles/file/kagiwow.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/a191d9d43509d6983da5552ce5002793/31645064780.pdfIn PDF document text
    • http://videotour24.com/data/fckupload/file/13091486338.pdfIn PDF document text
    • http://kiapelhrimov.cz/UserFiles/File/46219570114.pdfIn PDF document text
    • http://lakshimi-kaatsu.com/user_data/packages/default/imgfiles/94238192946.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139396f60e3a---buvenoxenidupulix.pdfIn PDF document text
    • http://toanthinh.vn/webroot/img/files/49940565216.pdfIn PDF document text
    • https://oasis-travel.ro/files/sufilujodagel.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_off0001188f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1188F 10896 bytes
SHA-256: 05ebb004c2a82ea6bded0fc842eb0151b2026f99f31560cca68abd920ebe8876
font_01_sfnt_off00013205.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13205 22452 bytes
SHA-256: 3f009b1f48aa8103c5215bd3d4d73a687c32c1d16657c27aaa823bbc1d1c1087
font_02_sfnt_off00016c31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16C31 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1