Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4f517445336989f…

MALICIOUS

PDF

68.4 KB Created: 2021-09-19 17:58:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4eeba5a456fe23d1268c30392acb0d0d SHA-1: 7c1c7b93371efe10304debed6a81468d74818492 SHA-256: b4f517445336989ff21f06d7805a5e8c7e82ed47f7d49299f36dfe2008c21d36
126 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and is identified as a link farm, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the presence of embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://pistant.ru/uplcv?utm_term=android+developer+crop+image PDF link annotation
    • https://at1apigroup3.com/contents/files/34238194203.pdfIn PDF document text
    • https://sealand-pptc.com/userfiles/file/mozibubidisivadalowamu.pdfIn PDF document text
    • http://imosa.asia/uploads/files/202109052154173967.pdfIn PDF document text
    • http://pmrs.ps/userfiles/file/91393901799.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/161427bf120888---86724114271.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/bizumutagepulonu.pdfIn PDF document text
    • http://anapro.com/ckfinder/userfiles/files/35869654573.pdfIn PDF document text
    • http://floramarble.com/uploads/17688089769.pdfIn PDF document text
    • https://renhedc.com/uploads/files/202109071454373958.pdfIn PDF document text
    • http://kythuatviet.vn/uploads/userfiles/file/zogewex.pdfIn PDF document text
    • http://gutachterbewertung.de/userfiles/file/mevabibebevijoxovivedunu.pdfIn PDF document text
    • https://yumasri.com/assets/ckfinder/userfiles/files/koronibedifuwuvilumo.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/1613a23b5b1b33---bokuporuloxibanoro.pdfIn PDF document text
    • https://franchise-vietnam.com/app/webroot/img/files/zorinirebivis.pdfIn PDF document text
    • https://ckeditor.pamlskovnik.cz/ckfinder/userfiles/files/73356337381.pdfIn PDF document text
    • http://greenhere.cn/upload/ckimg/files/202109081706185293.pdfIn PDF document text
    • https://confidence-ist.com/ckfinder/userfiles/files/pemiwirupugomomopen.pdfIn PDF document text
    • https://kaptenhoki.net/contents/files/jogarorafizuvipolowo.pdfIn PDF document text
    • http://mehmetrasimmutlu.com/icerik/file/91826295928.pdfIn PDF document text
    • http://k2plusinterior.com/userfiles/33817186625.pdfIn PDF document text
    • https://cahayamimpi1.com/contents/files/75336643702.pdfIn PDF document text
    • http://utcsp.rustyramone.com/uploads/files/rabatawukibijatipu.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_off0000ae8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE8B 10640 bytes
SHA-256: d3b02daf4254af8d6e24f0c2cb0df3ddbfeeb1e13221c6c1f38fe3d432029fbe
font_01_sfnt_off0000c69b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC69B 15060 bytes
SHA-256: 2bfead74ea300bc89053f4e944ecf9cfc4b4d4b0733113cb266459b201ec4273
font_02_sfnt_off0000ec52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC52 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1