Malicious PDF — malware analysis report

Static analysis result for SHA-256 553bdb491eab1d5c…

MALICIOUS

PDF

85.8 KB Created: 2021-09-20 12:55:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-01
MD5: de318cc3f47d248ac03ae9cd696a8955 SHA-1: ad903d71130e0e082960a91e8595e3171e1739e2 SHA-256: 553bdb491eab1d5cef338cca27b1df4a0e44aa0e4ecad46ddf0c85b1f7867a43
126 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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 https://mar3ol.com/Files/files/nufeparivirusamapumabufe.pdf In PDF document text
    • https://chataigne-cevennes.fr/imgs/files/wubemaforitovupeporikuto.pdfIn PDF document text
    • http://gesundimjob.at/images/content/files/43712494877.pdfIn PDF document text
    • https://livnica-metalurg.com/images/pages/file/45834091477.pdfIn PDF document text
    • http://tvkinter.com/file_media/file_image/file/tivininepo.pdfIn PDF document text
    • https://cowichanmusicfestival.com/userfiles/file/83186593432.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614824d128aff---35592894439.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/0227a7733b76025e6612b66a23c5aafc/69551879982.pdfIn PDF document text
    • http://peterpan1996.it/userfiles/files/96747577208.pdfIn PDF document text
    • http://123flower.doweb.kr/upload/files/wafon.pdfIn PDF document text
    • http://hzxgdz.com/images/upload/File/rujovigosepolovejupid.pdfIn PDF document text
    • http://heureka-cz.eu/files/67618448959.pdfIn PDF document text
    • http://baracenter.be/userfiles/file/94350236548.pdfIn PDF document text
    • http://aotwresort.info/ckfinder/userfiles/files/84775151669.pdfIn PDF document text
    • http://asupuro.com/upload/save_image/files/rinowamabetojotamib.pdfIn PDF document text
    • http://onnetsolution.in/userfiles/file/xuduzagepibukewapurin.pdfIn PDF document text
    • http://zh-huaxun.com/uploadfiles/files/tetusadalusadasusaxovame.pdfIn PDF document text
    • https://trouver-une-ssii.com/img/pics/files/zuxufidaxijegusatipuw.pdfIn PDF document text
    • http://gradn.ru/uploades/fckeditorfile/ligafifowobo.pdfIn PDF document text
    • https://zivotzaokny.eu/res/file/gijinixaronebakofol.pdfIn PDF document text
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/23852358575.pdfIn PDF document text
    • http://zaiger.ru/img/file/bezosotuzef.pdfIn PDF document text
    • https://penzionradvanice.cz/res/file/39796149695.pdfIn PDF document text
    • http://varosom.hu/userfiles/files/zuninuj.pdfIn PDF document text
    • http://dydlhx.com/upfiles/file///donigapasufuga.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210915_112747.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=mapy+seznam+pro+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_off0000e852.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE852 10576 bytes
SHA-256: ef9a7d0157719f0befd99ebb098906295e20bc651352f80118804fc22fa79732
font_01_sfnt_off00010071.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10071 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011883.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11883 19720 bytes
SHA-256: fd0a2ab8a91937d0660ed52bf21a879cb8d4f94acacf9ffd6e0de99f431f0bda