Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dce839a1be9de8f…

MALICIOUS

PDF

98.1 KB Created: 2021-09-13 15:36:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: cc720ae98230285d7608d8921d6a3b00 SHA-1: 86c9010f7296d6a67776dac9ce090f8dea1dd255 SHA-256: 8dce839a1be9de8f703e5b9f08b3dbdf088e5ad4382f5a6b3ff0a69169519cca
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains a large number of embedded URLs, many pointing to disposable domains, suggesting a link farm or phishing lure. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior. While no scripts were explicitly extracted, the presence of numerous external URIs and the overall detection profile strongly suggest the PDF is designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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 http://www.cbs-emballages.com/upload/file/zefofolis.pdf In PDF document text
    • http://clickvay.com/upload/files/73448397496.pdfIn PDF document text
    • http://lagrupacio.cat/file/puxadovetogodarod.pdfIn PDF document text
    • https://resulgame.com/calisma2/files/uploads/retef.pdfIn PDF document text
    • http://wx-bm.cn/upload/ckimg/files/202109021047386369.pdfIn PDF document text
    • http://ottomaniantextile.com/userfiles/file/magetujusuturiwaluxisox.pdfIn PDF document text
    • https://www.igescanada.com/ckfinder/userfiles/files/60639852809.pdfIn PDF document text
    • https://xenang-mitsubishi.com/fckupload/file/wugere.pdfIn PDF document text
    • https://ikuseikyokai.jp/ckmedia/files/36731986671.pdfIn PDF document text
    • http://pijntherapie.be/uploads/files/59907531258.pdfIn PDF document text
    • https://mimpiindah88.com/contents/files/966476157.pdfIn PDF document text
    • https://abcelectricalonlineshop.brilliantwebtech.com/userfiles/files/57992702854.pdfIn PDF document text
    • https://sklepbonus.pl/userfiles/file/96536984176.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/161317326386fc---ladaz.pdfIn PDF document text
    • http://thaide.org/userfiles/file/wajesikivos.pdfIn PDF document text
    • https://manage3.realtourvision.com/rtv/ckfinder/userfiles/images/files/genowokujivorigunala.pdfIn PDF document text
    • http://barahi.com/assets/userfiles/files/bigewefo.pdfIn PDF document text
    • http://gerastar.com/userfiles/file/xojakisireleseworupuru.pdfIn PDF document text
    • http://musicandyouapp.com/webupload/editorimg/files/67172761539.pdfIn PDF document text
    • http://ainut.fi/userfiles/file/27090427889.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ed93cddb96---sidedadamupezom.pdfIn PDF document text
    • http://czerwoneiczarne.pl/files/file/kopoxisawarafu.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/52299649197.pdfIn PDF document text
    • http://lsmtrontractor.com/upfiles/file/20210902214746.pdfIn PDF document text
    • http://yummyschool.com/_UploadFile/Images/file/fapox.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=chal+mera+putt+2+full+movie+online+123PDF 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_off000111e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111E5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000129fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129FC 10996 bytes
SHA-256: 80874dbd7d171dc7a43d25ea1d9120b593479f54fa2037089dbc7be0c975dd7a
font_02_sfnt_off0001436c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1436C 20796 bytes
SHA-256: 319434d77055c46099c783fcd08c0ef3d26d90b701937a0a267150070aeb2bbb