Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cf6b496839febf4…

MALICIOUS

PDF

88.0 KB Created: 2021-09-02 05:52:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 711cf906966ef14719fa267e810a3275 SHA-1: b805cd98a62b1803407bee54a84ba6469fb08034 SHA-256: 1cf6b496839febf46895c4461677422febdcf83aa9ea7c68f755ac13aace376f
156 Risk Score

Malware Insights

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

The PDF file contains a link farm directing users to multiple URLs, many of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of numerous links on disposable or compromised hosting reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/0jcr5s3ardddct74sunq3241eb/34806051729.pdf In PDF document text
    • https://toptenstudy.com/upload/files/BodyFile__60B8E3733AD9B.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160ec5141bbb11---63908016942.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/c0fcd7c5810c3d3324151ada9fd3e34c/wudetatir.pdfIn PDF document text
    • http://bradhelferlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/64795949361.pdfIn PDF document text
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/66171941089.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac4be8e8871---2743173379.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160907b31973e9---19125447378.pdfIn PDF document text
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/cntsohjgb0v1efat4mrgsb2oe3/20301428675.pdfIn PDF document text
    • http://xtra360.net/campannas/file/70663407616.pdfIn PDF document text
    • http://www.doctor-carpet.com/wp-content/plugins/super-forms/uploads/php/files/6jg7jhv7dto3672c65da46b8k5/satilowipikadufewimigijot.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160814e2d131dc---kekuxejaxemaligitupinuk.pdfIn PDF document text
    • https://rimsball.com/ckfinder/userfiles/files/lududojetodisesaxobotog.pdfIn PDF document text
    • https://burstallconrad.com/editor_files/file/3452438478.pdfIn PDF document text
    • http://deltastal.ru/userfiles/file/vedudodirinesoxumomuj.pdfIn PDF document text
    • https://saam.vn/images/content/file/gejatufazexikonur.pdfIn PDF document text
    • https://alutat.com/data/file/disevewimojojifel.pdfIn PDF document text
    • https://babetravelling.com/ckfinder/userfiles2/files/8725257762.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612d737cb4a0d---gofizalusomuwesixatir.pdfIn PDF document text
    • http://www.abcklima.hu//data/editorfile/lamenokuxomoxenukizilir.pdfIn PDF document text
    • http://nujhimachal.in/img/uploads/files/93652578812.pdfIn PDF document text
    • http://kunjipsc.com/uploads/files/dabosulokomusefuv.pdfIn PDF document text
    • https://marblobaths.ph/app/webroot/img/files/tejetutewodorodokowug.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=low+sodium+appetizersPDF link annotation
    • 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_off0000f558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF558 17180 bytes
SHA-256: 037b9ebe93546d2a8445b2bc0f4f13f421384314b047381ef9f33f1c734b36e7
font_01_sfnt_off0001223d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1223D 10608 bytes
SHA-256: daff9dd346a20e0cae5d55aeda4b4daa2a38672e3b5ad036b06b6250da717f84
font_02_sfnt_off00013a9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A9D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1