Malicious PDF — malware analysis report

Static analysis result for SHA-256 157b80a0d96bd8ec…

MALICIOUS

PDF

78.9 KB Created: 2021-09-14 02:29:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 28ec160393140043e1d4b91b6fab7cef SHA-1: 51c7f86a114ad6b498ca30327412f430fa6b3df0 SHA-256: 157b80a0d96bd8ec3931181d4c1e299f34e69adcb4c59886f57c192663038270
126 Risk Score

Malware Insights

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

The PDF document was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to host numerous links on disposable domains, a common tactic for phishing or distributing further malware. The embedded URLs point to various unknown PDF files, reinforcing the likelihood of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://shindah.com/images/ckeditor_img/files/60546329603.pdf In PDF document text
    • https://lawweb.info/mycms/admin/userfiles/file/jemupukemuwezalegikenobi.pdfIn PDF document text
    • https://takipbizde.com/calisma2/files/uploads/regogevuvidade.pdfIn PDF document text
    • https://kenkochaya.com/user_data/ckfinder/files/wakotugujefunesulugu.pdfIn PDF document text
    • http://sanzmendia.com/userfiles/files/funonejizunalekidawe.pdfIn PDF document text
    • http://veterinariacomportamentale.it/userfiles/files/tafesimoguzekewigakeva.pdfIn PDF document text
    • http://tunapvietnam.thietbiotoviet.com/Images_upload/files/nuzifidetoxedapenok.pdfIn PDF document text
    • http://lovec.bg/root/ckfinder/userfiles/files/69598526378.pdfIn PDF document text
    • http://sensitiva.fi/UserFiles/File/fupeleku.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file///kutetiwabawudaf.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fce5eba893---fonedewejad.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/97414917529be696a693faf9880e2fa7/turonuweredufu.pdfIn PDF document text
    • http://metabolizmusonline.hu/images/upload/file/lefapekuvebixami.pdfIn PDF document text
    • http://salt17.com/userfiles/files/gigivibol.pdfIn PDF document text
    • http://energosol.pl/images_cms/file/fazarukufese.pdfIn PDF document text
    • http://adirondackseafood.com/ckfinder/userfiles/files/topikixezebow.pdfIn PDF document text
    • http://adec-interiors.net/Uploads/file/54795927391.pdfIn PDF document text
    • http://khyljg.com/uploadfiles/files/77269638771.pdfIn PDF document text
    • http://cukrarnakolbaba.eu/obrazky/files/18172964723.pdfIn PDF document text
    • http://chocoenglish.com/_UploadFile/Images/file/jusevigiwemafajebun.pdfIn PDF document text
    • http://dison.cn/filespath/files/20210913142850.pdfIn PDF document text
    • http://tg-focus.ru/userfiles/files/25476132872.pdfIn PDF document text
    • http://thietbikhachsanvinhhung1.com/upload/files/sijivesinawuponiwazusa.pdfIn PDF document text
    • http://tulga.ru/editor/files/89526178433.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=how+to+share+files+between+android+and+windows+phonePDF 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_off0000ce56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE56 18204 bytes
SHA-256: 7819ae96a8c86eddc79ea89637ecc37bd52fb54c56ccdfdb36049d9cbc24c4f3
font_01_sfnt_off0000fcf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCF2 10812 bytes
SHA-256: f73be7f5155ddda495757091303ecfa3b581041fcd2be712af84b0ad84064f26
font_02_sfnt_off00011594.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11594 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1