Resource exhaustion in Twisted
CVE-2026-115776
Twisted is an event-based framework for internet applications, supporting Python 3.6+. Prior to 26.10.0rc1, twisted.words.protocols.irc.IRC.dataReceived retains all bytes received without a line feed in its per-connection buffer and applies no maximum line length. The twisted.words.service.IRCUser server subclass inherits this behavior, and buffering occurs before PASS, NICK, or USER authentication commands. An unauthenticated connection can continuously grow the buffer until the shared server process runs out of memory and drops all users. This issue is fixed in version 26.10.0rc1.
Vulnerability class: DoS (Denial of Service)
Published .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Twisted — versions < 26.10.0rc1
Weakness classification (CWE)
References
- github.com/twisted/twisted/security/advisories/GHSA-53xc-49m8-p798
- github.com/twisted/twisted/pull/12771
- github.com/twisted/twisted/commit/01f8cff7753c1edac132380b2ea939fa6bdbab30
- github.com/twisted/twisted/commit/ac90fb7b0ab73688a581fcd9a7c0577ec8ca3059
- github.com/twisted/twisted/releases/tag/twisted-26.10.0rc1
Frequently asked questions
- What is CVE-2026-115776?
- CVE-2026-115776 is a high-severity vulnerability in Twisted, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-10-23.
- How severe is CVE-2026-115776?
- High severity. CVSS v3 base score is 7.5 out of 10.