Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6ba98e7bdbadc99…

MALICIOUS

PDF

75.6 KB Created: 2021-08-31 20:10:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 940766cd1ffaa75992b2c4e0db6bbc44 SHA-1: 0d365b90ef2a186be63dddbdb533537945412fd3 SHA-256: a6ba98e7bdbadc993cc673c0f664abde7ab685ccad0fbe2a26e4f60a3358f28a
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The sample is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript and a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting it's designed to trick users into downloading further malicious content. The presence of a 'download button' heuristic further supports this phishing-like lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 8

  • 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.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://samngaimarble.com/html_upload/file/vexazowilidagere.pdf
    • https://discovercefalu.com/_data/images/file/37399554694.pdf
    • http://guchenes.com/d/files/25448551624.pdf
    • https://alihuata.com/userfiles/file/33825936472.pdf
    • http://garage-ys.info/js/upload/files/54544857116.pdf
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/1609474496729e---60054248290.pdf
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/b39d608519f0097b29089bf019e066c2/watufepilimifis.pdf
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/16088aa6ff14d5---37543772513.pdf
    • http://domosplast.hu/files/file/vuzanazaworozumetumojiw.pdf
    • http://apluskleaning.com/admin/images/file/3157822279.pdf
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f295850c58---lidevefezufowajapimebeno.pdf
    • http://nhs1966reunion.com/clients/1/1c/1ca8f1639ee69cd7806809ed3bcda9bb/File/86997102341.pdf
    • http://mictrogiang.com/userfiles/files/74166023068.pdf
    • https://x-software.cz/data/file/wekevasexupatozoxerole.pdf
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/itsoqnau10cg4sk294fggg71sh/31453196174.pdf
    • http://thepokeluau.com/uploads/files/zikoxenunu.pdf
    • https://www.karelo.com/uploads/File/93304940491.pdf
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/gov27u9g60i4b6d7us3lb74gg2/30895975850.pdf
    • http://tcurryproperties.com/konadnew/userfiles/file/12768251450.pdf
    • https://nbcmedia.vn/ckfinder/userfiles/files/98642023640.pdf
    • http://xn----7sbabaajmdfbk3ddf3azka3b6a2r.xn--p1ai/ckfinder/userfiles/files/rizezepenewojezeri.pdf
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/1607ddb6f62535---25356627873.pdf
    • http://xiaohecollege.com/d/files/26321860265.pdf
    • http://hnkingdee.cn/Files/file/2021527395.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=the+complete+cyber+security+course+volume+2+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_off0000c2bf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC2BF 16792 bytes
font_01_sfnt_off0000dad1.bin
4575c9baaf8195351d65cb34cb63b66c493cad9af5a1f825bed38aeaf366cf4d
pdf-font-stream PDF embedded font (sfnt) at offset 0xDAD1 16908 bytes
font_02_sfnt_off00010685.bin
de19426405ef665bd4e8b93129afd9b0ce437d9a768cb4855e898025d691bb24
pdf-font-stream PDF embedded font (sfnt) at offset 0x10685 11120 bytes