Malicious PDF — malware analysis report

Static analysis result for SHA-256 1865def817041de1…

MALICIOUS

PDF

74.4 KB Created: 2021-09-03 20:32:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 0c4696d6eca8614402a9e319a9a0120d SHA-1: a16a8395e08bd1c8c3b991cc58812043edf4d14e SHA-256: 1865def817041de14d8aae506ae7679f3862690e79c27024a27466b16e73d78d
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code or redirecting users. The numerous external URIs, many pointing to compromised CMS upload directories or disposable hosting, indicate a link farm designed to obscure the ultimate destination and evade detection. The ML classifier strongly suggests malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://coretry.ru/uplcv?utm_term=virginia+evans+grammarway+3+pdf PDF link annotation
    • http://ahkjt.com/upfile/file/ruresewavupojubotu.pdfIn PDF document text
    • https://grupo-bahia-real-estate.com/ckfinder/userfiles/files/76425155326.pdfIn PDF document text
    • http://rmgoals.com/userfiles/files/33079706588.pdfIn PDF document text
    • https://locoffice.ru/userfiles/file/42049131429.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a40fd0d6218---64291497291.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/bd6t7mh5a3i8lmptonjk83olkf/57851575350.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f71d51cee2a---vubolinazuketoniv.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095f81d1727f---xojid.pdfIn PDF document text
    • https://sfasg.jp/js/ckfinder/userfiles/files/nafipogojeseluroteke.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210519114807254.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160822be876cae---tugus.pdfIn PDF document text
    • http://terralis.eu/catalogue_dynamique/file/famezevizafokagatulijuxus.pdfIn PDF document text
    • http://szsahsh.com/uploads/files/86249003173.pdfIn PDF document text
    • http://stellarp.com/userfiles/files/zupubusurukanuvodiximabov.pdfIn PDF document text
    • http://churchtextile.com/userfiles/file/donabokuzogisob.pdfIn PDF document text
    • https://bokaichenyu.com/upload/files/83775648890.pdfIn PDF document text
    • http://pcserviszlin.cz/ckfinder/userfiles/files/kunorimotopaf.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/3446787d2982a3939b4482549293f699/jijumiwesariseti.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-5-13/20210513123533752164.pdfIn PDF document text
    • http://all-pass.com/folder/editor/file/japodagefozilarilux.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5efad522f---79007946296.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/khheq6ilqe6tjessmq8grfr7v6/kuwikawizuromefesiseti.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_off0000bf05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF05 10984 bytes
SHA-256: bef54dfe063aacc3292c571469631697bd1017e527daf258e9e22f1075b66ec8
font_01_sfnt_off0000d862.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD862 16868 bytes
SHA-256: 2f443f65c10b999330b9f0343864d8d7753ceb7353b117dad98ed4b2b5946dd4
font_02_sfnt_off00010403.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10403 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1