Malicious PDF — malware analysis report

Static analysis result for SHA-256 d854e8e71aab6ae3…

MALICIOUS

PDF

81.8 KB Created: 2021-09-01 16:28:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: fd2c3c052fa34e4741f90862ac7414aa SHA-1: cc3a0bd60e8756f153153c4e803e076fb574b540 SHA-256: d854e8e71aab6ae387a28508eb1b953b62ca366c8603517774b6f650047ffd0a
96 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to numerous PDF documents, some hosted on compromised WordPress sites. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a non-clustered link farm on disposable hosting, and the 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristic confirms links to compromised upload storage. The ML classifier also flagged this PDF as malicious with high confidence. These elements suggest the document is designed to distribute further malicious content or lead users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608a14d300b1a---zipotivizavo.pdf In PDF document text
    • http://candleelectricals.com/uploaded_files/userfiles/files/wefedoludoro.pdfIn PDF document text
    • http://studiolegaletrotta.eu/userfiles/files/80036007884.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/vulibirixaresaloxuj.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-5-24/20210524025307922786.pdfIn PDF document text
    • http://falerisztika.hu/tmp/78885101792.pdfIn PDF document text
    • http://www.amedna.com/userfiles/files/9469521066.pdfIn PDF document text
    • http://www.radio-kum.si/data/files/majusasenej.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/0acd7a0441f164dbd3edcf233ab7f687/zawutiwifa.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc4baa26da---zejebo.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609214d377036---wuzilelim.pdfIn PDF document text
    • https://jiptv.nl/wp-content/plugins/super-forms/uploads/php/files/b5njk7fd317rlpeh7m9qcrd63s/kelejusi.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/a70n3gpj7osart6gvosd9fglrd/54532225423.pdfIn PDF document text
    • http://tucsokszekszard.hu/images/news/file/54218444387.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094d33c0e0fe---fixux.pdfIn PDF document text
    • http://www.lnk-creation.fr/upload/file/nerorereretapugopaxulaz.pdfIn PDF document text
    • http://shengnabei.com/uploadfile/file///2021081601584552.pdfIn PDF document text
    • https://506hlapeta.com/files/file/52276131877.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca8703dd33---muwuwikoz.pdfIn PDF document text
    • http://airsoft1.ro/files/file/86343433137.pdfIn PDF document text
    • http://dep14kirov.ru/userfiles/file/23099072351.pdfIn PDF document text
    • https://alutat.com/data/file/19270796663.pdfIn PDF document text
    • http://atdawnwelift.com/userfiles/file/teluboso.pdfIn PDF document text
    • https://searchlink.org/userfiles//file/kapozukavedu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=bully+anniversary+edition+game+free+download+for+androidPDF 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_off0000da8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA8D 11116 bytes
SHA-256: 384e3d4712d487422b14a714426826194e2786a107cc7ac0f972547766249faf
font_01_sfnt_off0000f462.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF462 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010c74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C74 17504 bytes
SHA-256: ad0e33bd0f088852f31dbc6234bc3e8160c062bd82c65bc1699524be9aefb9b2