Malicious PDF — malware analysis report

Static analysis result for SHA-256 113aef5c1ebce861…

MALICIOUS

PDF

77.9 KB Created: 2021-09-23 11:36:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 5704012ad826966851adcb3b7dbdda1a SHA-1: 6fd734e78069e71ea6266cd599d3295098754de0 SHA-256: 113aef5c1ebce861a33f519c6f3a44b1f4fac0df879fb0c6e003f08db65cc151
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which are part of link farms hosted on compromised or disposable domains. The ML classifier strongly indicated maliciousness. The embedded JavaScript and link farm structure suggest an attempt to lure users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://archism.ru/uplcv?utm_term=android+os+7.0 PDF link annotation
    • https://tideandtigers.com/ckfinder/userfiles/files/24964813380.pdfIn PDF document text
    • http://agronlogistics.com/userfiles/files/zujawin.pdfIn PDF document text
    • https://faresaldabbous.com/uploads/files/gumiseviwutoli.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147164707a32---komotaxewinetu.pdfIn PDF document text
    • https://whitepalacegrill.com/userfiles/14194584647.pdfIn PDF document text
    • http://skisun.it/userfiles/files/51665871677.pdfIn PDF document text
    • http://industrialsupplies.pk/userfiles/files/93701906211.pdfIn PDF document text
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/73084604936.pdfIn PDF document text
    • http://educaholistica.com/resources/img/imagesck/files/71463663710.pdfIn PDF document text
    • http://vinhthuan.vn/upload/files/31665563313.pdfIn PDF document text
    • https://egyseg.eu/ckfinder/userfiles/files/rusulupeviregavexi.pdfIn PDF document text
    • http://etre-belle.su/images/file/gadenisugojupopotoluxured.pdfIn PDF document text
    • http://xn--80aiddhbkcq5bcaz.xn--p1ai/upload/files/tejosanuxidivav.pdfIn PDF document text
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/244fd9cba64d17f99de22eb8cdc538b0/nimivoleziteluwozo.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1613b4e5206923---51007127353.pdfIn PDF document text
    • https://vanphongphamhienluong.com/upload/files/vamuriditora.pdfIn PDF document text
    • https://www.opsclown.it/ckfinder/userfiles/files/wijanuvenimanas.pdfIn PDF document text
    • https://jechrina.gr/FCKeditor/userimages/file/sovobiwedem.pdfIn PDF document text
    • http://yuanhebiotech.com/upload/files/kataz.pdfIn PDF document text
    • http://tetrafluoro.com/upload/files/32898499742.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/2q7v8paaovb3e45oe1a51meo0e/vasapubakixu.pdfIn PDF document text
    • https://reaga.net/js/ckfinder/userfiles/files/nakibaguvidab.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_off0000cf18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF18 10024 bytes
SHA-256: 740a1ba95c9f0ec0ce043c24b8c832ee17d77eb6a0c3bc9dc0b751c58ff01b8e
font_01_sfnt_off0000e56c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE56C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fd7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD7E 17136 bytes
SHA-256: 3c392ee0fbe132808155e6a01be005d299d08e9cb297a58cf9829d846e2fc6b8