Malicious PDF — malware analysis report

Static analysis result for SHA-256 316ee4c60649ffe8…

MALICIOUS

PDF

82.1 KB Created: 2021-09-20 18:29:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 042ff834e67a5e833248ae117a616ca6 SHA-1: 1bc7d07919c33799a83a955bbbe093f9ec85856c SHA-256: 316ee4c60649ffe81cc7691e928c727a02b014d3a9790f7bcb3056ca5fea8624
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier strongly indicates malicious intent. The embedded JavaScript likely facilitates the redirection or exploitation process.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 http://yuc-fac.com/uploadfiles/20210912044517.pdf In PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/e911hqet5s7kb89ntv2mld57ef/79309521547.pdfIn PDF document text
    • http://paliukenas.lt/i/File/mewugevomikopebizi.pdfIn PDF document text
    • http://drairtools.com/ckfinder/userfiles/files/bisinup.pdfIn PDF document text
    • https://www.tyrtaios.gr/ckfinder/userfiles/files/58451014446.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/poia00uhl0m558cf2ln5gksjs7/9756304234.pdfIn PDF document text
    • http://etkenkalip.com/files/43977286830.pdfIn PDF document text
    • http://ekhoron21.mn/uploads/files/kijevofuvidagegulanudav.pdfIn PDF document text
    • https://palezieux.com/ckfinder/userfiles/files/xaxuwevoxekatedozupib.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/8342e2323b39f5d6fed7c1db3a3610b9/58828176235.pdfIn PDF document text
    • https://jmtours.co/aym_image/files/nosivekotusajameke.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135295643cc7---77307980143.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/sapovaw.pdfIn PDF document text
    • http://wxhsbl.com/ckfinder/userfiles/files/20210905_123339.pdfIn PDF document text
    • http://scuderia512.com/js/upload/files/12102827573.pdfIn PDF document text
    • https://viboot.traigiongthuha.com/ckfinder/userfiles/files/sujavufavovotisozavan.pdfIn PDF document text
    • https://all-stage-meditation.tw/uploads/files/6145c832cad3f.pdfIn PDF document text
    • https://dbjadow.pl/attachments/file/xikutitegomajul.pdfIn PDF document text
    • https://thietbivesinhsonhoa.com/webroot/img/files/65560083218.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/rituropasodazabo.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/16133a6138132d---82309896762.pdfIn PDF document text
    • http://studioagronomoserragiotto.eu/userfiles/files/nagaju.pdfIn PDF document text
    • https://worldpigment.com/image/upload/File/givadaraxusiruri.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=android+telefon+temas%C4%B1PDF 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_off0000d907.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD907 10544 bytes
SHA-256: df062c203e1b0d751e7643a8b57a5cdb0c20d581a503987ecd99da97ab8fa528
font_01_sfnt_off0000f0f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010909.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10909 19740 bytes
SHA-256: 19e2d3e2c1ab3e5f4b31cd0809f247f6aa7af067a8623399f01a31ef8f0d66aa