Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef5b0bddd8a7f5cb…

MALICIOUS

PDF

92.9 KB Created: 2021-09-19 12:02:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 0229f3df33a2a8e74a9d22dd25a1937c SHA-1: 0ab6af7dc15fb2b91cdfa3a12287fe2b7d5b00f4 SHA-256: ef5b0bddd8a7f5cbdb172761f72157e18fa58b615b05b99b83684f878f49162b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm on disposable hosting. The embedded URLs point to various domains, suggesting a phishing or malware distribution campaign. Although no scripts were explicitly extracted, the PDF structure and heuristic findings strongly suggest it is designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://allytemp.ru/uplcv?utm_term=donkey+kong+country+snes+roms PDF link annotation
    • http://studiocastigli.eu/userfiles/files/mibeboripogopifaxaxe.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/777d6cd84af56d274fb71a0c190a18dd/buvagiwexudukakelofozalo.pdfIn PDF document text
    • http://starfishdowney.com/uploads/files/xobitopipelozusubi.pdfIn PDF document text
    • http://registermycompany.in/admin/userfiles/file/gawewolaxubefen.pdfIn PDF document text
    • http://xn--h1acbpobggs.xn--p1ai/data/files/9723405236.pdfIn PDF document text
    • http://vswet.ru/f/5512043668.pdfIn PDF document text
    • https://wilocom.ro/ckfinder/userfiles/files/ruzifovazef.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/nokusojelatabaj.pdfIn PDF document text
    • http://farmaciafoglia.eu/userfiles/files/36511614375.pdfIn PDF document text
    • http://vagtteam.com/userfiles/Files/runijawamepazoz.pdfIn PDF document text
    • http://greddy.com/admin/common/ckfinder/userfiles/File/sijegivepikol.pdfIn PDF document text
    • https://istanajp.com/contents/files/bugosatamobixepiru.pdfIn PDF document text
    • http://nenorm.com/files/files/49098684053.pdfIn PDF document text
    • https://tatvan.in/userfiles/file/7328289371.pdfIn PDF document text
    • http://radiosalsa.fr/php/rs/filesupload/file/fisokadinobe.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/e02db6c22e5904e0541d4dbf92cff789/23560572272.pdfIn PDF document text
    • http://www.fred-robin.com/ckfinder/userfiles/files/xiwijowenizanipun.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/76297153938.pdfIn PDF document text
    • https://istanajp2.com/contents/files/sugamajezaz.pdfIn PDF document text
    • http://mebelhotel.ru/userfiles/files/45756516496.pdfIn PDF document text
    • http://bienbao.org/uploads/files/55234723657.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210911060424048.pdfIn PDF document text
    • http://artdental.hu/editor_up/91910186868.pdfIn PDF document text
    • http://101eyewear.com/luutru/files/zaxogegoxakewazomijoreb.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_off0001014e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1014E 10580 bytes
SHA-256: 258eeef2e6a84526a43bf52854b8c1565b7bf6dfdbe756da9fa94a6bb1410fc8
font_01_sfnt_off0001198c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1198C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001319e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1319E 19388 bytes
SHA-256: 4db7f5f6b40f98c1c939284240e30b8b97fdc604c77f95fe38aed7c5a6b9997e