Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
The russh package, versions before 0.64.1, is vulnerable: its agent protocol server spawns a task for each 5-byte constraint lifetime record in an added key request, and those tasks are not cleaned up if the request later fails. An attacker who can speak the agent protocol to the server, such as a local process with access to the agent socket or a remote SSH server the user connects to with agent forwarding, can use a stream of small constrained add-key requests to drive large memory growth until the agent crashes. Upgrade to russh 0.64.1 or later. The source gives no workaround.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 4.3 | Medium | 3.1 | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0035, the 28th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:24 UTC First seen by agentprime
- 31 Oct 2026, 14:24 UTC Confirmed by OSV