Malicious PDF — malware analysis report

Static analysis result for SHA-256 da928cba70266dcb…

MALICIOUS

PDF

78.4 KB Created: 2021-09-27 20:32:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2d28892cfe40aa6d14c135e7588f5109 SHA-1: f9bd150b7481f9359d3c327b0da58ff6791c04e7 SHA-256: da928cba70266dcb80a53fe4a3f708d0624b0700da3a52beb4b9fbed4ea054f7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable domains and form a link farm, a common tactic for distributing malicious content or phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9844

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://ntvietnga.com/upload/files/kimukod.pdf In PDF document text
    • http://comp-art.ru/userfiles/file/penolirunuxumome.pdfIn PDF document text
    • http://theurbanbazzaar.com/userfiles/file/maraparabexidifuz.pdfIn PDF document text
    • https://toliveinchristjesus.ceosale.catholic.edu.au/application/third_party/ckfinder/userfiles/files/fagadukiwomixureruxoburo.pdfIn PDF document text
    • https://elearnhouse.com/userfiles/file/xiwivulilawepububidol.pdfIn PDF document text
    • http://xn--5dbfbdrd7azav1bcx.com/sites/default/files/file/2535899387.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/rokitizasawiw.pdfIn PDF document text
    • http://barsugo.com/ckfinder/userfiles/files/kixivimukafutiriru.pdfIn PDF document text
    • http://pegasomeeting.medcoast.net/ckfinder/userfiles/files/ratozomavana.pdfIn PDF document text
    • https://www.rougeindigo.com/ckfinder/userfiles/files/lofewiratigumiji.pdfIn PDF document text
    • http://suamanhinhlcd.net/userfiles/file/bugojarozete.pdfIn PDF document text
    • http://free-note.kr/files/fckeditor/file/15832930936150192409f17.pdfIn PDF document text
    • http://alarm.pl/userfiles/file/mirawenibemutavimuriki.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614e7ca5d605e---badegobarotiwujidusevewa.pdfIn PDF document text
    • http://www.valathors.com/ckfinder/userfiles/files/radijotigexobulezanorixit.pdfIn PDF document text
    • http://zaiger.ru/img/file/rukewigituzebigebapi.pdfIn PDF document text
    • https://bientannamhuy.com/wp-content/uploads/files/supotafomo.pdfIn PDF document text
    • http://studioaba.net/userfiles/files/2643586634.pdfIn PDF document text
    • https://alubiasdetolosa.com/files/galeria/files/42998480877.pdfIn PDF document text
    • http://maasmartcity.com/userfiles/file/68244581066.pdfIn PDF document text
    • http://grandioso.asia/editor_upload_image/file/dokerotitit.pdfIn PDF document text
    • http://nhakhoanhantin.com/media/ftp/file/71300547876.pdfIn PDF document text
    • http://alothongtin.com/upload/FCK/file/11146426787.pdfIn PDF document text
    • https://servingltda.com/userfiles/file/xorizetimoxunomamogoziji.pdfIn PDF document text
    • http://detaycopymatbaa.com/userfiles/file/18410572343.pdfIn PDF document text
    • https://ystechpro.com/nbloom/fckuploads/file/ruvirex.pdfIn PDF document text
    • https://distriparkbotlek.nl/userfiles/files/35185529315.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=cara+setting+microphone+di+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_off0000c831.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC831 18700 bytes
SHA-256: 063727fae455e6dd642efea2282670baac72401e8b0a1fa29825fc36ac276e36
font_01_sfnt_off0000f8f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F6 10944 bytes
SHA-256: 7283f23c2aa2d2afbbb35f8f06fcc164cf8e4857657ddd89bf5864f0ec499351
font_02_sfnt_off000111f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1