Malicious PDF — malware analysis report

Static analysis result for SHA-256 b53e3df4f79c51a6…

MALICIOUS

PDF

87.3 KB Created: 2021-09-18 10:36:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 226fe6ad6273cb66b3ce8a123057a696 SHA-1: d308185d0341d41bdbcd59d962b4e72162fdcb84 SHA-256: b53e3df4f79c51a60ee745e5c95067e34cff646103ed2e31b7d123477b8fb247
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier indicating maliciousness. It contains numerous external URIs, many pointing to disposable hosting, suggesting a link farm or phishing lure. The presence of embedded URLs and the overall structure strongly indicate it's intended to redirect users to malicious websites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://smidgel.ru/uplcv?utm_term=best+violin+app+for+android PDF link annotation
    • http://hermandadperdon.es/userfiles/file/17977126359.pdfIn PDF document text
    • http://www.supair-lux.hu/ckfinder/userfiles/files/ramubomabolamatizo.pdfIn PDF document text
    • https://eol.org.pe/ckfinder/userfiles/files/1913298484.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/64649839101.pdfIn PDF document text
    • https://fokusmedia.com/images/uploads/89830021588.pdfIn PDF document text
    • https://vantainoidia.vn/ci/userfiles/files/61243554302.pdfIn PDF document text
    • https://h1t-urlaurora1-turbo.com/contents/files/93268200091.pdfIn PDF document text
    • http://xetaihyundai.net/upload/files/dadiderivuzevigibafor.pdfIn PDF document text
    • http://xn--hazrdner-r4a10d.com/alisveris/yollanan_resimler/file/geluxewiduzux.pdfIn PDF document text
    • http://sovaimm.it/userfiles/files/48854733550.pdfIn PDF document text
    • http://travelport.pl/userfiles/file/75914964259.pdfIn PDF document text
    • https://flomogroup.com/upload/files/88062952398.pdfIn PDF document text
    • http://palestraarkadia.it/userfiles/files/8831895281.pdfIn PDF document text
    • http://cctechlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/97539174263.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/431e393456b5f23ef5ff4c158e5520c5/27189563892.pdfIn PDF document text
    • https://ispartaprefabrik.com/ckfinder/upload/files/20400684811.pdfIn PDF document text
    • http://nwatchonline.org/userfiles/file/4676942207.pdfIn PDF document text
    • http://ardechetendancebrut.fr/userfiles/ardechetendancebrut.fr/file/86352690699.pdfIn PDF document text
    • http://abwbaltimore.com/uploads/files/29672266945.pdfIn PDF document text
    • http://marsalanoleggio.it/userfiles/files/fepibak.pdfIn PDF document text
    • http://telegid.tv/userfiles/file/vubexebe.pdfIn PDF document text
    • https://stollerco.com/testingsites/advantage_aviation/assets/media/file/tigubim.pdfIn PDF document text
    • http://chengzechem.com/upload/files/serekeratufevek.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_off0000f15d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF15D 10612 bytes
SHA-256: 085d1ac968dfa3b5e99f9912289368e3df34afd318f28c78d1fed7fce1eb86eb
font_01_sfnt_off000109cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000121dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121DD 17624 bytes
SHA-256: b87e55c0478c67608c27d505be55d5e0a524e2bd786161204a7ce3ac7bfb5063