Malicious PDF — malware analysis report

Static analysis result for SHA-256 e529d7caea8b0099…

MALICIOUS

PDF

81.2 KB Created: 2021-09-19 02:23:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: cad360ced5f396371ed54acc901be5ad SHA-1: 0f55ed13dda27f99487f189265f12ea2c210fefb SHA-256: e529d7caea8b009975093bb920a9f045229a193d57a628b4c4db25fe8cadb3d8
126 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous external URIs, many pointing to disposable hosting and employing UTM parameters, suggests a link farm designed to redirect users to potentially malicious download sites. The document body, though heavily obfuscated, contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create PDFs from web content, further supporting the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://garglob.ru/uplcv?utm_term=download+zarchiver+for+pc PDF link annotation
    • http://gayaarchi.com/userfiles/file/20210918020803.pdfIn PDF document text
    • https://ever-progress.dacola.com/upload/files/fenuzusowaxomivarun.pdfIn PDF document text
    • https://harteron.ee/userfiles/file/24584718382.pdfIn PDF document text
    • http://bwc.lt/i/72765471674.pdfIn PDF document text
    • https://ubitanduk.com/contents/files/83536065120.pdfIn PDF document text
    • http://thaoduocvn.com/userfiles/image/file/55065798776.pdfIn PDF document text
    • http://philipp-haberland.de/images/upload/file/nofimatenud.pdfIn PDF document text
    • https://blokhol.com/upload/files/tesol.pdfIn PDF document text
    • https://radio-clipa.ro/userfiles/file/85667079962.pdfIn PDF document text
    • http://giovanninociti.com/userfiles/files/jetabanalepa.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/0db542d049807353edbdce2f896c83cb/38273366123.pdfIn PDF document text
    • http://ceroki.com/image/files/ligarulozu.pdfIn PDF document text
    • http://chinalabware.es/d/files/guvotevelaresukaxofobik.pdfIn PDF document text
    • https://mepho.hu/ckfinder/userfiles/files/bibafopolerutasetowitilov.pdfIn PDF document text
    • http://i-p-p-c.com/ckfinder/userfiles/files/vixowasigega.pdfIn PDF document text
    • http://abbuffalowings.com/uploads/files/medaj.pdfIn PDF document text
    • http://sieuthimaynhapkhau.com/upload/files/virilerevufapukotawilogef.pdfIn PDF document text
    • https://safrano.pl/userfiles/file/20913659392.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/eh9hot68o95m26kv30pdp1vuq2/73004880890.pdfIn PDF document text
    • https://zohopin.com/calisma2/files/uploads/44743111750.pdfIn PDF document text
    • http://werkkledingverkoop.nl/images/docman/files/mowivexunidenobogapuv.pdfIn PDF document text
    • https://zhongzing.com/uploads/files/202109130104037045.pdfIn PDF document text
    • https://tramtron.vn/uploads/files/files/potelepabamazuz.pdfIn PDF document text
    • https://kiptep.ru/file/repenipamuwopif.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/pedolumoxatoropibitafa.pdfIn PDF document text
    • http://kirakuramen.com/uploads/files/74685647244.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_off0000d9da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F1 10664 bytes
SHA-256: f32a1737560cf23f86ec81903414b7d87f021c933e53983210c08669901b0b9e
font_02_sfnt_off00010a56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A56 17628 bytes
SHA-256: f73a6836382c5acc8cc689f3f33e13c671e92650c2ee91750b03c5cd7e7bad96