Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e5a51afa602de1a…

MALICIOUS

PDF

78.5 KB Created: 2021-09-06 07:51:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 320c4752604d91c2f7da345d795ecfa1 SHA-1: 383c2f028f3b4eb05f6424ab449c05df205a56c5 SHA-256: 4e5a51afa602de1a20290f62229e523f3c36447cd4b4340e1884f8f51871c5df
156 Risk Score

Malware Insights

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

The file is a PDF document that contains a link farm pointing to multiple external websites, many of which are hosted on compromised CMS platforms or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of numerous links, including one to a compromised WordPress upload, suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://salwangurugram.com/files/lanumibek.pdf In PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/4r037msqvpt19c4n6205jud7r2/fexefetogezozorijesuz.pdfIn PDF document text
    • https://medicabg.com/uploads/wysiwyg/files/37749857754.pdfIn PDF document text
    • https://incense888.com/uploads/files/202108210447173886.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/482c8fafd3ce7d2f8deb642d155835bf/80520370139.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/gosofenig.pdfIn PDF document text
    • http://eastbrunswickliving.com/clients/77672/File/99719366487.pdfIn PDF document text
    • https://infypos.com/infyposcms/media/tibifofogiduzesiwodiwoniv.pdfIn PDF document text
    • http://asirakademi.com/resimler/files/1106845768.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/202407a82caaf9e25ce4a5adca058cf0/60695748181.pdfIn PDF document text
    • https://doluhosting.com/calisma2/files/uploads/bawizaxa.pdfIn PDF document text
    • http://119hero.kr/userData/board/file/16118504033.pdfIn PDF document text
    • http://inhome360.ru/admin/ckfinder/userfiles/files/31121608491.pdfIn PDF document text
    • http://music-saikung.com/ckfinder/userfiles/files/75150558009.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160dda234a3d25---gobifogar.pdfIn PDF document text
    • https://wonwon.taipei/photo/file/xizaseve.pdfIn PDF document text
    • http://ksnjl.com/userfiles/files/99598913351.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607aa0c532997---64732427680.pdfIn PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/a3hf91aun9k4s8tvvf7pmnqrhn/tobamukijakegufena.pdfIn PDF document text
    • https://egyseg.eu/ckfinder/userfiles/files/33413122850.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=transmission+and+distribution+notes+pdfPDF 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_off0000d1a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A8 16336 bytes
SHA-256: eb81d23475f9479d921bdfc40a0791fcac491cfcf0393c2942a79ff979babe4d
font_01_sfnt_off0000fbe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000113f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113F7 10816 bytes
SHA-256: a419c4aaea1b7b0ae3752bd51b8a875fa3ea1fc0e47689338775d60ceb2889cd