Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca4d7dd6689fcd40…

MALICIOUS

PDF

89.6 KB Created: 2021-08-13 17:46:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: b36ff66c6129e14f0fc2e7d5f1a46e7f SHA-1: 7c77daf624d90117b19ef0b11a6837174dc78c19 SHA-256: ca4d7dd6689fcd405b8ac23fa034e79f6807296ef1ec459530a33ea0bd5a8304
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains a link farm pointing to multiple compromised WordPress sites, likely intended to host malicious content. The ML classifier strongly indicates maliciousness. Although no scripts were directly extracted, the PDF structure and embedded URLs suggest an attempt to lure users to external, potentially compromised, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16081f426620ed---20455438942.pdf In PDF document text
    • https://panama4d.com/contents//files/posabe.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/160b86eeb9a342---515543045.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///15547820974.pdfIn PDF document text
    • http://carszana.com/image/upload/File/68540698765.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/mujuzebosojoninatujazaw.pdfIn PDF document text
    • https://www.aeap.com.br/ckfinder/userfiles/files/zakoluweroxonakabilabote.pdfIn PDF document text
    • https://catequesisnavarra.org/guiarte_userfiles/files/66189786446.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c42dbd7e820---22453793646.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7e193cb06e---gigatuvedesuf.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b4609a66b5a---41602350112.pdfIn PDF document text
    • https://etre-cheval.fr/Applications/MAMP/htdocs/etre%20cheval/news_pix/file/27453416370.pdfIn PDF document text
    • http://synergytaekwondo.com/click2buy_newp/userfiles/file/jajowixa.pdfIn PDF document text
    • http://vet-arrighicolangelicristilli.eu/userfiles/files/71337831203.pdfIn PDF document text
    • http://droprint.my/home/ququ4923/public_html/userfiles/file/mevuwosabulodaturebule.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607230ed2c85d---jibidulem.pdfIn PDF document text
    • https://primewestelectrical.com/wp-content/plugins/super-forms/uploads/php/files/bfff5c4f386a4453af1d29701cc4a85b/fabiforape.pdfIn PDF document text
    • http://ongnuocdenhat.com/upload/files/lamubebafiganipupej.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609185a5ce505---misisoxisi.pdfIn PDF document text
    • http://jedzenie365.pl/ckfinder/userfiles/files/29662838304.pdfIn PDF document text
    • http://skomi.ru/img/files/file/40327219353.pdfIn PDF document text
    • http://www.jfac.kr/ckfinder/userfiles/files/mivapawef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=calculadora+de+ecuaciones+diferenciales+ordinarias+onlinePDF 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_off0000f4c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4C2 10500 bytes
SHA-256: e3203e5bcc582e21ffe2a64800e6f2bf9161cde7561e546f2ba28148ae804371
font_01_sfnt_off00010cba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CBA 19344 bytes
SHA-256: ea35a16f816fbba41bb9722d965e2a707e0c93a9fd749c21f9f5f1999efc0142
font_02_sfnt_off00013e95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E95 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1