Malicious PDF — malware analysis report

Static analysis result for SHA-256 4313a5269f79acc2…

MALICIOUS

PDF

90.2 KB Created: 2021-06-28 05:19:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e1d9e24b683c45ad78cf2857a6dcfc3b SHA-1: 95910bd1ab942e174f3276ef7b5c46bb1004d436 SHA-256: 4313a5269f79acc20d79e33b80ac02df69d2b4062658e12898b746d697eca351
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised CMS upload storage and disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery through these links. No scripts were extracted, but the structure itself is the attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://synerhu.ru/uplcv?utm_term=vygotsky+and+play
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/oi0ij9pafjeueiv1ou9p9u2iu5/gususibikenexeladimeveju.pdf
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce2422a657---nazujewomaragobisosareg.pdf
    • https://carparts-fixture.com/file/file/kutasononazemufileja.pdf
    • https://diphong.com/uploads/derebamesoromedu.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a9d3981c3cb---29267551818.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/16072f0df41413---bibide.pdf
    • https://quangcaonoithatgiahung.com/admin/webroot/upload/image/files/ponasiginotifumijimevez.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/af3000tsnd2tv3p66d65s2lobd/sabirub.pdf
    • http://www.tomasjelinek.com/img/pub/file/83512640834.pdf
    • https://cplastik.cz/data/cms/file/86619313545.pdf
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160842cf6906fc---pegepixapoduzefelu.pdf
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078ce43b1f26---61901340268.pdf
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/160725a45a4bbe---64038779007.pdf
    • http://kaushalacademy.org/ckfinder/userfiles/files/86280677160.pdf
    • http://ultraljud.nu/bild/files/1908194823.pdf
    • http://ofipapel.org//ckfinder/userfiles/files/60256508186.pdf
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0ca19bc7f4---mumowunulukejuzotizoxes.pdf
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/s5lae2n8cl9iusl258r6iss3ur/1597806259.pdf
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087b6d903f7b---kekudajavokutupujozid.pdf
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f128fbbcc6---89832243890.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/aqsphub9t66hn7d2j7fi9rm9j3/3273067459.pdf
    • https://e-lightingcontrols.com/wp-content/plugins/super-forms/uploads/php/files/d703dee7eee77dfc2f9a7e10295076dd/64323991027.pdf
    • http://mynigaoe.com/upload/file/20210517073246.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fe18.bin
b58b1df4c7ffcc056ba56290947280b47e81f54b073e1631e084a659dcc55279
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE18 17656 bytes
font_01_sfnt_off00012c6d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C6D 16792 bytes
font_02_sfnt_off00014484.bin
d4ea59cbd83c564ef35a96460680fb92b64b387b8381333da7d8202054e304a0
pdf-font-stream PDF embedded font (sfnt) at offset 0x14484 10420 bytes