Malicious PDF — malware analysis report

Static analysis result for SHA-256 311e37f5e24977d8…

MALICIOUS

PDF

85.9 KB Created: 2021-09-02 06:57:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 35b0a87c46f5bc5e9729a8f387cb924a SHA-1: 28cba29bdb007528ba7b6d0d2f171d60ab00ed5c SHA-256: 311e37f5e24977d86c3375dea3b9d4ad02a64ac1843fe6e07e452e5a1d1d8a18
96 Risk Score

Malware Insights

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

The ML classifier strongly indicated maliciousness, and multiple heuristics identified the PDF as a link farm. The embedded URLs point to compromised CMS uploads and disposable domains, suggesting an attempt to lure users to malicious sites. No scripts were extracted, but the structure itself is designed to facilitate malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://btc-ltd.com/upload/file/ripisipukerasagokejal.pdf In PDF document text
    • https://carea2plus.com/wp-content/plugins/super-forms/uploads/php/files/294e27ea0b795cf35a0693f3940322b6/57348797227.pdfIn PDF document text
    • http://kovovyroba-nosniky.cz/UserFiles/File/33282061325.pdfIn PDF document text
    • http://waukeganeast1980.com/clients/877304/File/9379997265.pdfIn PDF document text
    • https://landbar.com/upload/files/dalawozujir.pdfIn PDF document text
    • http://cornucopiafrederick.com/uploads/files/judodopiguziditavelurix.pdfIn PDF document text
    • https://cornwallstaffagency.com/userfiles/file/dadiwigowatefebiluf.pdfIn PDF document text
    • http://hayatteknoloji.com/webimage/file/8091575068.pdfIn PDF document text
    • https://alianzatours.com/imagenes/file/xutetanexorokexope.pdfIn PDF document text
    • http://przystaneknida.pl/data/aktualnosci_imgs/file/tevidikoxix.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16088f940c85b7---57294489304.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606feb816d9e0---wisuju.pdfIn PDF document text
    • http://xn--rssx31a7tec6p.com/upload/userfiles/files/20210814082419.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078852915dd1---sebomubo.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160947f3a4a89b---rupototeb.pdfIn PDF document text
    • http://ongxoanhdpe.vn/upload/files/77277887492.pdfIn PDF document text
    • http://dansecyr.ca/pdf/file/lebekope.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c12cbb6ef38---97890380960.pdfIn PDF document text
    • http://consade.com/userfiles/file/ninejigomub.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16086ce39a8241---selorubemajodawar.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/2d19309daa14329304332bb5ff476f98/42988626441.pdfIn PDF document text
    • https://ilcaminodaugo.it/file/nitemi.pdfIn PDF document text
    • http://d4svancouver.com/clients/c/c8/c8601140a4283eb9b700f388a83987a3/File/nemam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=vitamin+d+injection+dosePDF 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_off0000ec8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC8F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000104a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104A6 10484 bytes
SHA-256: d43637cd14bcddf96dde57e2afdd38e8e4b073fa8f17b3bd7f9bb8976d6054ec
font_02_sfnt_off00011c6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C6A 17380 bytes
SHA-256: 0079763f1d74114c77e76e0465a09c8a1bddc9803820069e886a4c1bf7f070eb