Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c41fd2f29720c21…

MALICIOUS

PDF

86.7 KB Created: 2021-09-17 02:32:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: dc0714418833d7f41a41371630b80685 SHA-1: cda87394561face9893657c016b99fbe040a3bdf SHA-256: 3c41fd2f29720c214d81c7a66d237ce414206cdd3fba6efdc9843fecdd1610bf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs that form a link farm, with several pointing to potentially compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using such PDFs for SEO manipulation or to host malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9930

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://elitacasa.it/images/file/tepafixuvu.pdf In PDF document text
    • http://tokyoracing.hu/userfiles/file/43139292648.pdfIn PDF document text
    • http://luckdidea.com/ckfinder/images_store/files/70415836912.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/cn5d4q18hi5mco1od53qs8m19p/jifonatuxixam.pdfIn PDF document text
    • http://vhktn.at/images/content/files/guxuk.pdfIn PDF document text
    • http://ahjygjg.com/upload_fck/file/2021-9-3/20210903181447416820.pdfIn PDF document text
    • http://lauraestetica.com/userfiles/files/49196760555.pdfIn PDF document text
    • http://studiostocchi.eu/userfiles/files/ragewi.pdfIn PDF document text
    • http://cncforginghammer.com/d/files/vagij.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/2m4bf45oef3ifgrtmic8kf9k9k/49687200728.pdfIn PDF document text
    • http://citra.cl/userfiles/file/satoxapeditedug.pdfIn PDF document text
    • http://asea-admin.com/_userfiles/file/20210908080548.pdfIn PDF document text
    • https://ladymamashop.com/uploads/files/202109110404223506.pdfIn PDF document text
    • https://medicentrumnz.eu/medicentrum/files/file/jinozezutok.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/13078792457.pdfIn PDF document text
    • http://dobre-jaja.com/Upload/file/11885669481.pdfIn PDF document text
    • https://mrpressconsulting.com/UserFiles/file/wibom.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d2af11414e---66611354468.pdfIn PDF document text
    • https://raguvosbaldai.manovonia.lt/images/files/89464269111.pdfIn PDF document text
    • http://bamor.org/userfiles/file/fatelujokejamuzafil.pdfIn PDF document text
    • http://turnyras.lt/Files/file/pupovodat.pdfIn PDF document text
    • http://www.sun-green.eu/ckfinder/userfiles/files/rakimekejutasi.pdfIn PDF document text
    • http://rigdrilling.org/userfiles/file/10395694940.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=car+parking+mod+android+1PDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d475.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD475 10468 bytes
SHA-256: 4907387cf1cd1390538cea4684fc6895a09f79578952e7a4afb70af4c001554e
font_01_sfnt_off0000ebf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF2 17324 bytes
SHA-256: 548f67c181e7ef935a1b691473a8c535140b8013afb42bd57a67bd79217f9079
font_02_sfnt_off000105c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00011ddb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DDB 18212 bytes
SHA-256: fb2021453c2751d6149fadff0ee5fdb2d4087d909ffe61cffac758861adf11dd