Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb49e831090d4503…

MALICIOUS

PDF

73.0 KB Created: 2021-09-24 05:03:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 7eeffc1b5389d6f3bcae2dbcfb4abe68 SHA-1: 3a6561b3d909dbc95cede6789f23de2331df472b SHA-256: bb49e831090d4503857a8ae6a2264af4b7381e50dc06c8d696ec932dad860045
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to disposable domains, and is flagged by ML classifiers and ClamAV as malicious. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of creating numerous small PDFs linking to distinct, potentially malicious hosts. While no scripts were directly extracted, the nature of the embedded URLs suggests an intent to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://royalrep.com/userfiles/files/fikatewolujilofe.pdf In PDF document text
    • http://kbinteriery.cz/userfiles/file/38049700697.pdfIn PDF document text
    • http://studioingegneriavaragnolo.com/userfiles/files/19871650950.pdfIn PDF document text
    • https://skinrepublic.vn/webroot/img/files/gopolajazenejo.pdfIn PDF document text
    • http://jyjjapan.jp/files/ckeditor/files/buzal.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/161498ad220786---39961203821.pdfIn PDF document text
    • http://historia-bfured.hu/userfiles/file/dezufaworakesejejiwaxo.pdfIn PDF document text
    • http://zdravi-kromeriz.cz/files/file/1202037011.pdfIn PDF document text
    • http://seattledesis.com/fckeditor/file/vuripoteretutalire.pdfIn PDF document text
    • http://mitsubishilongbien.vn/images/ckeditor/files/kupuvusabu.pdfIn PDF document text
    • http://coutleelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/rexawuno.pdfIn PDF document text
    • https://taucaotoccatba.vn/images/news/files/kubazozezomebulofawa.pdfIn PDF document text
    • http://raczcsalad.hu/files/pojomadabukut.pdfIn PDF document text
    • http://dr-temt.ru/images/file/dajudikewu.pdfIn PDF document text
    • http://dokumsuzgec.com/userfiles/files/rilokogutiwul.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140cd8a52287---51867054859.pdfIn PDF document text
    • http://ithalattagarantibelgesi.com/resimlerfiles/zoridov.pdfIn PDF document text
    • http://kfbma.org/files/fck/file/latefanime.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-6/20210906034832518531.pdfIn PDF document text
    • http://timandlor.com/userfiles/file/280186602.pdfIn PDF document text
    • https://deltaguvenlik.net/userfiles/file/faridabevodozazufi.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/2021921759549428.pdfIn PDF document text
    • http://brcassociati.com/userfiles/files/logijibuzu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+dial+extension+on+androidPDF 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_off0000bdda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDDA 16292 bytes
SHA-256: d6bd3638424bb81f9a7d0ae15066c392b181a1a2066775bb8ea9061a0b7045de
font_01_sfnt_off0000e6f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ff0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF0D 10420 bytes
SHA-256: af2b7d0357fe053b7dc62431e1a21f216d938d5ec28f15f831ed8551b34773fd