7.5

CVE-2026-102823: eugeny russh Improper Input Validation

CVSS: 7.5v3.1HighDeferred
AliasesGHSA-47hw-gvq5-r2gmDEBIAN-CVE-2026-102823UBUNTU-CVE-2026-102823
Published 29-09-2026Last modified 02-10-2026
Open JSON

Vulnerability summary

CVE-2026-102823 is a high (CVSS 7.5) Improper Input Validation vulnerability in eugeny russh. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 16.8% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.26%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 1
RHSA-2026:74586

Timeline

  1. 29-09-2026
    PublishedVulnerability first disclosed.
  2. 02-10-2026
    Last modifiedVulnerability information updated.

Description

Russh is a Rust SSH client and server library. Prior to 0.63.1, client_read_authenticated in russh/src/client/encrypted.rs forwards CHANNEL_DATA, CHANNEL_EXTENDED_DATA, CHANNEL_EOF, CHANNEL_CLOSE, CHANNEL_OPEN_FAILURE, CHANNEL_SUCCESS, CHANNEL_FAILURE, and CHANNEL_REQUEST subtypes exit-status, exit-signal, and xon-xoff to public client::Handler callbacks without confirming that the ChannelId belongs to a channel the client opened and established. A malicious SSH server can send lifecycle events for predicted, unopened, unconfirmed, or released channel identifiers, causing application panics or corrupting command completion and exit-code tracking. This issue is fixed in version 0.63.1.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.26%

Chance of exploitation in the next 30 days

Percentile

17%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

30-09-202620-10-2026
EPSS score
0.26%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Crates.Io1 product
  • russh< 0.63.1
Debian1 product
  • rust-russh< 0.64.1-1
Eugeny1 product
Ubuntu1 product
  • rust-russhAll versions (No fix recorded)

4 vendors · 4 products

References

8 links