Malicious PDF — malware analysis report

Static analysis result for SHA-256 51ff3824da569cc0…

MALICIOUS

PDF

89.1 KB Created: 2021-09-18 03:27:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 962992ae013efa9f3ba5fc24964aaafd SHA-1: 8d7583feed7707334fb19a9eeb0035fb4f8ba1ce SHA-256: 51ff3824da569cc055e4d0e0c06bf2afaab39a394b7ddc0aca94fea86a37c991
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm or phishing lure. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicates a deliberate attempt to obscure the true malicious intent behind a large number of redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://oembag.com/uploads/files/202109131708543865.pdf In PDF document text
    • http://esangsok.com/upfile/files/daxuj.pdfIn PDF document text
    • http://lionsmarsala.it/userfiles/files/9932776872.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/0ad79c0ba5ae7d2b4ed358bcfba2801c/lukupe.pdfIn PDF document text
    • https://taxfirma.com/userfiles/file/89021423285.pdfIn PDF document text
    • http://lactopad.com/uploads/files/46444988502.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/xesalipuguwabuvixiduxuru.pdfIn PDF document text
    • http://yamamatoen-wanwan.jp/ckfinder/userfiles/files/60572237175.pdfIn PDF document text
    • http://gimhaejazz.com/fckeditor/userfiles/image/tabitukeregexetixomuwa.pdfIn PDF document text
    • https://resttour.com/images/userfiles/files/90771951934.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd8a05bab4---moparogidadudomidepodesow.pdfIn PDF document text
    • http://yyfxsw.com/upload/files/79549168960.pdfIn PDF document text
    • https://eownauto.com/uploadpic/files/nuweguninisi.pdfIn PDF document text
    • https://dotcomtravelegypt.com/userfiles/files/wolasemaxujusemurorifa.pdfIn PDF document text
    • https://galaxy-training.com/userfiles/file/rikizito.pdfIn PDF document text
    • http://gocreate.termall.pl/upload/fck/file/98692061801.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/55741219237.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/161312fe7494c8---sapenap.pdfIn PDF document text
    • http://dansecyr.ca/pdf/file/1394764543.pdfIn PDF document text
    • https://jaurrieta.net/USERFILES_JAURRIETA/files/44788431710.pdfIn PDF document text
    • http://jafra-com.at/userfiles/file/41643642040.pdfIn PDF document text
    • https://www.vita-organic.eu/admin/ckfinder/userfiles/files/3656527501.pdfIn PDF document text
    • http://synergienetwork.net/userfiles/file/wekutenal.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=free+aimbot+fortnite+pcPDF 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_off0000f790.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF790 10544 bytes
SHA-256: 1d4aeedad9cf8cf64c4721d46d291b053fdeeee920f1e78db7f5180889b468a1
font_01_sfnt_off00010f53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F53 18248 bytes
SHA-256: 4fccbe710a252309945b6692e23755fcab0199d29c9e33026846557612ddfb88
font_02_sfnt_off00013eab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EAB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1