Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c8a251d63ea5a93…

MALICIOUS

PDF

88.1 KB Created: 2021-09-05 00:58:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 75f2dcd7a9a08f17f6484c124858d6ba SHA-1: 5486005936f56e6a17013cb9ec6fe947a47b276e SHA-256: 7c8a251d63ea5a937f36f16e6aab0480713786ca4ea4d3df00d17fc714f29b77
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://cuanhomkinhtoanthang.com/media/file/83134514014.pdf
    • http://gloexdr.com/wp-content/plugins/super-forms/uploads/php/files/3953b21ffb270e35aa151467d15d10e7/dizufizofixizawumarifale.pdf
    • http://pphu-joanna.pl/fckpliki/file/87370816515.pdf
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/c9321c535c91ce134d988bfc052a950c/62645448100.pdf
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e1be5d14ea1---19199910083.pdf
    • http://psychologyforeverybody.com/ckfinder/userfiles/files/71495307402.pdf
    • http://nfc-lampang.com/user_img/files/25405886147.pdf
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c1341581433---90239102379.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16078166933409---sutuselupusabetob.pdf
    • https://aslplastic.com/ckfinder/userfiles/files/nirimodamizokumikabumege.pdf
    • http://belniig.by/public/file/waxetojivaxex.pdf
    • http://arenabilardo.com/data/_files/17293160361.pdf
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f01369ab34---bovefifegobanuxaze.pdf
    • http://xn--42-6kcdlkbomh7beggito5p.xn--p1ai/userfiles/file/jokunitojemu.pdf
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/a2jcobvtkd80m5qnl97k8kaisv/13622447582.pdf
    • http://www.alex-vasilkov.ru/images/wisdom/file/modedefi.pdf
    • http://artospace.com/pics/file/64778300863.pdf
    • https://kfmaccounting.com/webroot/img/content/files/korabunisokezosaneb.pdf
    • https://aimara-bg.com/userfiles/file/jigukodimovafo.pdf
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab93f5b5460---vuzudufuropubelavijojumu.pdf
    • http://www.erealitysolutions.com/tennisontario/assets/appsadmin/js/ckfinder/userfiles/files/segilutajasedow.pdf
    • http://altinay-law.com/images/file/bozukewe.pdf
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1608038c1eefa8---43371009904.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=evga+nu+audio+manual
    • 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_off0000ee34.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE34 16792 bytes
font_01_sfnt_off00010646.bin
c8c5ca12df7f8ac1efe96777cd6bc08087fc7edcf30b6f83a4fcbac912d426e2
pdf-font-stream PDF embedded font (sfnt) at offset 0x10646 20716 bytes
font_02_sfnt_off00013c27.bin
705d0c22a35b6c536bb0d901be4021110e1a030ac0ec048fbcdb0265ce9fdaa2
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C27 10240 bytes