Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9a1e110331a23de…

MALICIOUS

PDF

68.5 KB Created: 2021-09-30 11:36:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 41213b8f43b76d93be8f993c5b0889db SHA-1: 1ea9eb3763c13dc44cf22e92b318d245dcf8709b SHA-256: c9a1e110331a23dec0dbdb844aeffc7839fe97d711aaa46e08bd2a433c8fb6ed
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for executing malicious code within PDFs. It also exhibits characteristics of a link farm, with numerous URLs pointing to external resources, some hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • 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://krisoc.ru/uplcv?utm_term=toga+himiko+live+wallpaper
    • http://weiddy.com/uploads/files/202109050714298677.pdf
    • https://jeevandeepspecialcare.com/ckeditor/ckfinder/userfiles/files/fagojudeji.pdf
    • http://ropesadventure.com/d/files/60538300951.pdf
    • https://automatisme-portail-bordazzi.fr/userfiles/fichiers/77001220452.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16152dd1fe3381---nexirevaku.pdf
    • http://chunmianxian.com/upfolder/e/files/20210921192520.pdf
    • http://gustosandvic.com/ckfinder/userfiles/files/zabaxekimawuxuxasilewikew.pdf
    • https://creteservices.com/FCKeditor/userimages/file/24013750315.pdf
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/856609dd83e5f22c96ebeeb93d7ecf00/janoduvuxal.pdf
    • https://www.sensormaticltd.com/app/templates/js/ckfinder/userfiles/files/84723990921.pdf
    • http://daydeothe.vn/rich_editor/file/14141574797.pdf
    • http://apcmagon.com/userfiles/xeguvefamirugataz.pdf
    • https://kovrdom.ru/sites/all/sites/default/files/file/64250310730.pdf
    • https://wfca-czech.cz/temp/userfiles/files/molabuzasubirobezilavax.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/16152e69eda72b---87011297863.pdf
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613aa8e1a822f---19237089041.pdf
    • http://www.accl-calibration.com/login/ckfinder/userfiles/files/32919870386.pdf
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/5abd038747ae3478c23cb6bcc7ab47c9/78835140156.pdf
    • https://muratay.nl/userfiles/file/7484815564.pdf
    • http://25630638.kad.tw/kads/ckfinder/userfiles/files/49713580598.pdf
    • http://tensoinox.com/userfiles/files/fivalixizulusuzekamekaviv.pdf
    • https://myclubowners.com/userfiles/files/raligojavanalezazatumu.pdf
    • http://camara.acessoainformacao.org/uploads/ckfinder/files/zebupatojifi.pdf
    • https://catequesisnavarra.org/guiarte_userfiles/files/63328085981.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_off0000b006.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB006 16792 bytes
font_01_sfnt_off0000c81d.bin
e245e11b42accbec01b02534b880f39635668343aa146e5d31f77462754aec37
pdf-font-stream PDF embedded font (sfnt) at offset 0xC81D 10536 bytes
font_02_sfnt_off0000e023.bin
5c971d4388270b7d170ed0bf1cdf6c3f79214d697941dff8149f70fd7784aff2
pdf-font-stream PDF embedded font (sfnt) at offset 0xE023 14568 bytes