Malicious PDF — malware analysis report

Static analysis result for SHA-256 157165a18b73a57e…

MALICIOUS

PDF

68.4 KB Created: 2021-09-26 21:04:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b05a928d127e49c726523c442ae95d5d SHA-1: 6f4d616db6f99d382a0aac00d290125d68a4c1d6 SHA-256: 157165a18b73a57e5550acc62b9b3108f61aa0bbfbbcd151543685766d6051b0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of embedded URLs and the nature of the heuristics indicate an attempt to exploit users through deceptive links, likely as part of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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://huntic.ru/uplcv?utm_term=how+to+open+xapk+file+in+android+phone
    • https://plentis.eu/ckfinder/userfiles/files/jexifujafesaje.pdf
    • http://vuatoyen.com/uploads/userfiles/file/8383361212.pdf
    • http://sspvjd.com/FileData/ckfinder/files/20210908_0134850329834D83.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613331b8f25a6---146727528.pdf
    • http://bastola.org/userfiles/file/41914136481.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/s5d750jliafsklqffg4k6rhmo8/desitudowezuvajonugonubi.pdf
    • https://anhhuynoithat.com/asset/files/pawakogezesoza.pdf
    • http://neonatal-surgery.ru/userfiles/files/30950961336.pdf
    • https://olterus.com/contents/files/xazekopexavigom.pdf
    • http://lovesenergy.nl/file/19367994457.pdf
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/42f3856fd4334cddd1419f0db7d746a6/pavibof.pdf
    • http://maskaevlawyer.ru/userfiles/file/91200113378.pdf
    • http://agrocare.hu/ckfinder/userfiles/files/613425286.pdf
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/161508e41c130c---82139553960.pdf
    • https://limadelimon.com/images/file/xitewapogopimeregi.pdf
    • http://markaz-e-durood.com/EditorImages/file/38268379573.pdf
    • http://inannamsao.com/uploads/files/werebateviviwigunosiboj.pdf
    • https://fullprotec.com/ckfinder/userfiles/files/48218247612.pdf
    • http://qiangka.com/ckfinder/userfiles/files/xosewega.pdf
    • http://aptekarynek.pl/zdjecia/fck/file/gifipijagu.pdf
    • https://eastmangroupllc.net/ckfinder/userfiles/files/47167304981.pdf
    • http://congseng.com/uploadfile/files/vedidulugelogumali.pdf
    • http://zulassungsdienst4you.de/bilder/file/68269794660.pdf
    • http://guojingmall.com/userfiles/file///nabaxarefudusi.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000aeb0.bin
8d3e1c0c36c224bce8e80f7c6c2d0f2cd60d4d3f65378f69033336961c92e9fc
pdf-font-stream PDF embedded font (sfnt) at offset 0xAEB0 14560 bytes
font_01_sfnt_off0000d361.bin
2b80b1b7cd805d7cc7070c9fb81271d9544fdf21b04c094772104d9d89b26607
pdf-font-stream PDF embedded font (sfnt) at offset 0xD361 10700 bytes
font_02_sfnt_off0000ebdf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBDF 16792 bytes