Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1918af7f0537013…

MALICIOUS

PDF

81.0 KB Created: 2021-09-16 16:25:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 03400b90d855a0a014b67afa39b9713f SHA-1: 8a4533668f1415014600b31d74144578f4f38484 SHA-256: b1918af7f0537013f874a4d866f7088448680bafd499f77d0ca43b9286b11286
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable domains, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is a common technique for exploiting PDF vulnerabilities or redirecting users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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://interel-rus.ru/test/sites/default/files/file/75564947741.pdf In PDF document text
    • http://graphicyazd.com/ckfinder/userfiles/files/wibisifemugotavalixavo.pdfIn PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/79140236608.pdfIn PDF document text
    • http://nuraski.pl/wsg/userfiles/16852281167.pdfIn PDF document text
    • http://elitakhealing.com/ckfinder/userfiles/files/mokotasudemabiniferudisaj.pdfIn PDF document text
    • http://fivelscope.net/fckimages/25877198756.pdfIn PDF document text
    • http://itnetworkconsultingsf.com/helpdesk/app/webroot/img/userfiles/files/80250690219.pdfIn PDF document text
    • https://bouveau-consulting.com/userfiles/file/18265466720.pdfIn PDF document text
    • https://cuisinescartier.ca/upload/editor/file/28174401488.pdfIn PDF document text
    • http://lamgi.pl/ckfinder/userfiles/files/tojakokexevaj.pdfIn PDF document text
    • https://www.highlandernepal.com/assets/ckfinder/userfiles/files/99111595975.pdfIn PDF document text
    • https://maxtarget.by/ckfinder/userfiles/files/vilirewutun.pdfIn PDF document text
    • https://strategieb2b.com/userfiles/file/57308926953.pdfIn PDF document text
    • https://memorybg.net/app/templates/js/ckfinder/userfiles/files/virigowu.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613673f3132fe---60550074517.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/23193264252.pdfIn PDF document text
    • http://naim.naparts.com/images/fck/file/xefaziripapedorufagup.pdfIn PDF document text
    • http://www.dfdtrading.sk/ckfinder/userfiles/files/favobubilufexi.pdfIn PDF document text
    • https://matfreklam.com/calisma2/files/uploads/timaxukanubefulokep.pdfIn PDF document text
    • http://lingvastar.z-i-g-z-a-g.com/userfiles/files/bituvimexeligurunivin.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/43f481bc8ec5846efbe771f8e8c5e70d/bukefaxezizotazabojorofob.pdfIn PDF document text
    • http://buyyoutubecomments.com/ci/userfiles/files/85386173172.pdfIn PDF document text
    • https://www.kuwaitpolyurethane.com/ckfinder/userfiles/files/81021131283.pdfIn PDF document text
    • http://autoescuelatosal.com/galeria/files/3794346929.pdfIn PDF document text
    • https://grupa-energia.pl/attachments/file/mijufanevikasonigimenu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=instruments+used+in+classical+periodPDF 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_off0000d997.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD997 16928 bytes
SHA-256: ae303ab0c306cfefcce849f41c9d217ea8fc2fe35e2928378551b62c1d481941
font_01_sfnt_off0001055d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1055D 10724 bytes
SHA-256: a251f58a54826dc9b2116ccf8819188fd6000d632d785efa4c091f82945b3f9e
font_02_sfnt_off00011df6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DF6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1