Malicious PDF — malware analysis report

Static analysis result for SHA-256 b276db652332a51f…

MALICIOUS

PDF

80.6 KB Created: 2021-09-22 14:04:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4ef644bb460a6eb95a6dc09e548c3dd3 SHA-1: 638f51fa00f4c4cf23bce1b8daaf4f1e13edaf12 SHA-256: b276db652332a51f75dd8fc33655f368c1000cfb48ca72308b9a1c0a63b49e77
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The sample is a PDF file flagged by ClamAV as a phishing trojan. Heuristics indicate embedded JavaScript and a social engineering lure prompting the user to install a browser extension or update. This suggests an attempt to compromise the user's system or steal credentials. The presence of embedded JavaScript points to potential execution of malicious code.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://regimhotelierbucuresti.com/images/userfiles/vijegexoderawazuxovofivez.pdf In PDF document text
    • http://hglobaltour.com/FileData/ckfinder/files/20210914_A366EAFA15B234BB.pdfIn PDF document text
    • http://snuhonors.com/userfiles/file/moninutemaxaforozafatilu.pdfIn PDF document text
    • http://yuemeism.com/uploadfiles/files/33573983950.pdfIn PDF document text
    • https://idroilektriki.gr/files/file/32048692162.pdfIn PDF document text
    • https://panama4d.com/contents/files/fomojunen.pdfIn PDF document text
    • http://spostojow.pl/userfiles/file/90463584697.pdfIn PDF document text
    • https://dptech.vn/uploads/files/61482739310.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/13279609230.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///wupenakanopoposisoruzata.pdfIn PDF document text
    • https://bestofbucerias.com/upload/file/53479850461.pdfIn PDF document text
    • http://www.sanruou.com/app/webroot/uploads/files/74948278072.pdfIn PDF document text
    • https://zoomkish.com/basefile/zoomkishcom/files/jexevutesubutin.pdfIn PDF document text
    • https://ofertaromania.ro/ckfinder/userfiles/files/sanuponaviti.pdfIn PDF document text
    • http://midospa.com/upload/files/11435228563.pdfIn PDF document text
    • http://humidorio.de/ckfinder/userfiles/files/xaxojonojuminojironax.pdfIn PDF document text
    • http://stellarp.com/userfiles/files/16152052667.pdfIn PDF document text
    • https://vanvoorst.info/uploaded/file/bemidoroturamakil.pdfIn PDF document text
    • http://mikomisushi.com/uploads/files/99727542219.pdfIn PDF document text
    • http://fskyok.com/uploadfile/files/50830958000.pdfIn PDF document text
    • http://ysenb.kr/board/file/editor/file/pawoduvuw.pdfIn PDF document text
    • https://www.tulsarad.com/my_content/js/ckfinder/userfiles/files/50015065152.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=advanced+html+and+css+pdfPDF 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_off0000d7e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eff5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFF5 17184 bytes
SHA-256: 07744963a7783337acddc2a8d1e5f5ace6c163a79819ae8cebaeb1bc982586ae
font_02_sfnt_off00011c8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C8E 10620 bytes
SHA-256: 1330e8ca1eb9e19ed108462cb7b597678665c1bec73fe4b0245728aae06dd7b9