Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9d2effed30016d1…

MALICIOUS

PDF

76.9 KB Created: 2021-09-23 09:07:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6fae7a93331725da0efa7eb4acdb09ef SHA-1: f39ec51878c541acb9aec5b4e580ff909fe2a736 SHA-256: f9d2effed30016d1c081e72f6f351d1e7435faa5b6299b74a2258abff53311cb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://synerhu.ru/uplcv?utm_term=what+is+kodi+on+android+box PDF link annotation
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/2030a2daa35d2f63bae82e5c88a8212e/vexufujibusu.pdfIn PDF document text
    • https://wroclaw-effatha.pl/grafiki/file/56782831861.pdfIn PDF document text
    • https://www.psk.com.au/application/third_party/ckfinder/userfiles/files/xofefedax.pdfIn PDF document text
    • http://phunphu.com/userfiles/file/luxevopararupa.pdfIn PDF document text
    • http://topbuild.net/content/xuploadimages/file/21959401580.pdfIn PDF document text
    • http://fygl.net/uploads/file/100322596430.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/a8a7db16d31540392fbdf9436abee9e5/3588233531.pdfIn PDF document text
    • https://magiccat.pro/ckfinder/userfiles/files/ridunegozapa.pdfIn PDF document text
    • https://digiconelectronics.com/media/letuvu.pdfIn PDF document text
    • https://lawweb.info/mycms/admin/userfiles/file/32768369048.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146c0a85f2e6---47401178297.pdfIn PDF document text
    • http://studiodara.eu/userfiles/files/kagunobiruxevo.pdfIn PDF document text
    • http://mgbig.com/upload_fck/file/2021-9-23/20210923052122281618.pdfIn PDF document text
    • https://telliogluhukuk.com/userfiles/file/saxekusomebesagolakoz.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a5ff8848e1---20349186488.pdfIn PDF document text
    • http://borik.customreal.sk/data/files/gasifasavufalobox.pdfIn PDF document text
    • http://china-baby-clothes.com/d/files/42938951582.pdfIn PDF document text
    • https://cortemadera.com/wysiwygfiles/file/wilekokipesoli.pdfIn PDF document text
    • https://altaamir.ipixpms.com/Rapport/public/assets/ckfinder/userfiles/files/muborewapuxijoxibejad.pdfIn PDF document text
    • https://presstone.hu/userfiles/file/wovot.pdfIn PDF document text
    • http://tivati.com/uploads/userfiles/file/2456868611.pdfIn PDF document text
    • https://www.weboonline.com/ckfinder/userfiles/files/62504996366.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_off0000c57f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC57F 18652 bytes
SHA-256: 9564ed2cf89b8b000e221411937607b3de37576c25c133b98d4210bc97876d7b
font_01_sfnt_off0000f5b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B5 10492 bytes
SHA-256: 06ad6f403f41c165ac1be4eb7c43f05037041d80cb364c3bea11386c4ad6d762
font_02_sfnt_off00010d87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D87 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1