Malicious PDF — malware analysis report

Static analysis result for SHA-256 50dfd8ef0f5d608c…

MALICIOUS

PDF

83.2 KB Created: 2021-09-03 18:57:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4e362ae45562736ce0b34937b5d022c0 SHA-1: f90529124043182b09a44714ce19ee8acc327cf0 SHA-256: 50dfd8ef0f5d608cd997ab46ee9857eb188544f4a8025df22e01c283b5f8305a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites and disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm strategy, likely to obscure malicious destinations or for SEO poisoning. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://ketchas.ru/uplcv?utm_term=the+ranger%27s+apprentice+book+10+pdf PDF link annotation
    • https://teenvolunteer.org/wp-content/plugins/super-forms/uploads/php/files/03913bb9797fd97be5eb41ba7996d74f/88416914984.pdfIn PDF document text
    • https://vietnaminsight.biz/ckfinder/userfiles/files/dalutamejalizirovezipez.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/licpp7b2nq5ni2rb0nor97qmlo/pasopiji.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b1ab94453b---puwidotivunaduwikomolez.pdfIn PDF document text
    • http://citysuji.com/ckfinder/userfiles/files/diraderesowosogapogatowi.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/sapmjfmuk9lim7mc43286eve1h/buwewunemut.pdfIn PDF document text
    • http://palazzodiaz.com/userfiles/files/pupimigesusilirerezemug.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/12e26ff2de2734dbd3c7fb9309610acc/xezaxi.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/wivajikuvuxiki.pdfIn PDF document text
    • https://o2opr.co/userfiles/files/remolotu.pdfIn PDF document text
    • https://roshindelivery.ae/userfiles/files/49587807851.pdfIn PDF document text
    • http://kkitv.com/images/upload/File/40178806766.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/61400067131.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/da2af24c35878ac9d21998f8f0bcda03/82140999123.pdfIn PDF document text
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/53ab3fa20317605d08f9509118c191ac/54485488517.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9b20bc2bb---kunujotisunodafegizewej.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160834ec91bf78---24580166040.pdfIn PDF document text
    • https://victorybear-info.com/userfiles/files/bigapikimovazogivuraxu.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/rm6knnfj9iauldq6pt57bh2hof/65565378753.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083a8e934590---gebasulegataz.pdfIn PDF document text
    • https://karapinarinsaat.net/userfiles/upload/file/koxubiledozox.pdfIn PDF document text
    • http://dlastudenta.org/Upload/file/78225267402.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/5273204b51f0a35c8fb3c415971e6be6/12616447363.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_off0000db2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB2B 11256 bytes
SHA-256: e777f0adca41e0106bc50c588541d2cba4e2232a4313dfaba886aaf40ab061ce
font_01_sfnt_off0000f52c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF52C 18992 bytes
SHA-256: d7c020b7eb0959bd6a8417f17b7b6656c95ea9363e3cb6a2e7433e518bea4695
font_02_sfnt_off0001271f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1271F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1