Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8fe7915e9869aa4…

MALICIOUS

PDF

84.8 KB Created: 2021-09-21 01:47:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3d77c9fe967c6e8717adc7e76cdf91bc SHA-1: 43d70dcdebacae24af3c3f4f108a43a6c148ea95 SHA-256: f8fe7915e9869aa471b97838c840e368854a8e88a2e97665603e35c3353b2ef4
126 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 a large number of embedded URLs, many of which point to disposable hosting or are part of a link farm, indicating a strong intent to redirect users to potentially harmful sites. The presence of numerous external URIs and the ML classification strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://krisoc.ru/uplcv?utm_term=how+to+sync+text+messages+android PDF link annotation
    • http://www.samuitns.com/image/upload/File/rufowelitejomu.pdfIn PDF document text
    • https://anukulagrotech.com/ci/userfiles/files/76197866586.pdfIn PDF document text
    • http://parejalecaros.com/adjunto/upload/fck/files/zukusepewetowob.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/45955466899.pdfIn PDF document text
    • http://rhondachem.com/d/files/boguzexeguvibilevetifenep.pdfIn PDF document text
    • http://wohntraumgmbh.at/54820366574.pdfIn PDF document text
    • http://cwesp.biz/upload/file/melat.pdfIn PDF document text
    • http://apexibd.com/uploads/fck_uploads/file/melipudiro.pdfIn PDF document text
    • https://aldwalia.com/userfiles/files/nalapelomasudobixafuvipev.pdfIn PDF document text
    • http://studiogiovannone.com/userfiles/files/98600261985.pdfIn PDF document text
    • https://masihpt2.com/contents/files/rimekew.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613297e9abe04---pateponoxumusubirarenateb.pdfIn PDF document text
    • https://bostoncake888.com/UserFiles/files/pisovaperozux.pdfIn PDF document text
    • https://www.bramfordgc.co.uk/ckfinder/userfiles/files/dezaxadusa.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/32387418711.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/fagokazasejemakuv.pdfIn PDF document text
    • http://cauthangdep24h.com/upload/files/mepelub.pdfIn PDF document text
    • http://materialdeestudo.top/userfiles/files/baxowezobibutejanid.pdfIn PDF document text
    • https://nasikampung.info/contents/files/78812923066.pdfIn PDF document text
    • https://homestayhoian.thamtuddt.com/uploads/image/files/40475325959.pdfIn PDF document text
    • https://bursac.net/userfiles/file/guxadutewubemuvej.pdfIn PDF document text
    • https://lnpro.in/ckfinder/userfiles/files/vuvafuwimute.pdfIn PDF document text
    • http://fasson.vip/images/editor/files/ripeworodekepefexeda.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133df7e72b8a---levekazatubajidixex.pdfIn PDF document text
    • 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_off0000e576.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE576 10960 bytes
SHA-256: 246090fd9836ee5e5b116a290473820e48b34d39a4d751c956f440c06f78989d
font_01_sfnt_off0000fec2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000116d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D4 18152 bytes
SHA-256: 9529c6661c2f8b71533ecce08632b9a970bf20692f37753399f3f5603c4c6ee9