Nixpkgs security tracker

Permalink CVE-2026-42304

7.5 HIGH

CVSS version (CVSS): 3.1
Attack Vector (AV): Network (N)
Attack Complexity (AC): Low (L)
Privileges Required (PR): None (N)
User Interaction (UI): None (N)
Scope (S): Unchanged (U)
Confidentiality (C): None (N)
Integrity (I): None (N)
Availability (A): High (H)
Modified Attack Vector (MAV): Network (N)
Modified Attack Complexity (MAC): Low (L)
Modified Privileges Required (MPR): None (N)
Modified User Interaction (MUI): None (N)
Modified Confidentiality (MC): None (N)
Modified Scope (MS): Unchanged (U)
Modified Integrity (MI): None (N)
Modified Availability (MA): High (H)

updated 1 month, 1 week ago by @LeSuisse Activity log

Created suggestion 1 month, 1 week ago
@LeSuisse ignored
3 packages
- python312Packages.pytest-twisted
- python313Packages.pytest-twisted
- python314Packages.pytest-twisted
1 month, 1 week ago
@LeSuisse accepted 1 month, 1 week ago
@LeSuisse published on GitHub 1 month, 1 week ago

Twisted: Denial of Service (DoS) in twisted.names via Crafted DNS Compression Pointer Chains

Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.4.0rc2, the twisted.names module is vulnerable to a Denial of Service (DoS) attack via resource exhaustion during DNS name decompression. A remote, unauthenticated attacker can exploit this by sending a crafted TCP DNS packet containing deeply chained compression pointers. This flaw bypasses previous loop-prevention logic, causing the single-threaded Twisted reactor to hang while processing millions of recursive lookups, effectively freezing the server. This vulnerability is fixed in 26.4.0rc2.