Güvenlik Zafiyet Raporu

CVE-2026-63311

NLTK before 3.10.0 (affected versions <= 3.9.4) contains a server-side request forgery (SSRF) vulnerability in the validate_network_url() function in nltk/pathsec.py. The _resolve_hostname() helper catches OSError and ValueError during socket.getaddrinfo() and returns an empty list; when DNS resolution fails, the validation loop executes no IP checks and the function fails open, allowing urlopen() to proceed without validation. An attacker who can trigger DNS resolution failures or use DNS rebinding can bypass SSRF protections and reach restricted network resources, including cloud metadata endpoints (e.g., 169.254.169.254).

CVSS5.3
RiskMEDIUM
Yayın22.08.2026
KaynakNVD

Açıklama ve Etki

NLTK before 3.10.0 (affected versions <= 3.9.4) contains a server-side request forgery (SSRF) vulnerability in the validate_network_url() function in nltk/pathsec.py. The _resolve_hostname() helper catches OSError and ValueError during socket.getaddrinfo() and returns an empty list; when DNS resolution fails, the validation loop executes no IP checks and the function fails open, allowing urlopen() to proceed without validation. An attacker who can trigger DNS resolution failures or use DNS rebinding can bypass SSRF protections and reach restricted network resources, including cloud metadata endpoints (e.g., 169.254.169.254).

Referanslar

Güvenli Doğrulama Notu

Bu sayfa saldırı gerçekleştiren payload'lar çalıştırmaz. Doğrulama; etkilenen ürün/sürümün envanterden kontrol edilmesi, üretici güvenlik duyurusunun incelenmesi ve güncellemenin uygulanması üzerinden yapılmalıdır.