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TI-2026-65512 Aliases CVE-2026-102823GHSA-47hw-gvq5-r2gm

russh: Client-side channel-scoped Handler callbacks fire for channel IDs the client never opened

Priority HIGH 72CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00317 24th percentileScored 2026-11-07
Fix Fixed russh (Eugeny): 0.63.1russh (crates.io): 0.63.1Red Hat: 1 advisory

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
Eugenyrusshbefore 0.63.10.63.1Patch availableCNA
—russh (crates.io)before 0.63.10.63.1Patch availableGHSA-47hw-gvq5-r2gm
  • russh VendorEugeny Affected before 0.63.1 Fixed in 0.63.1 Patch available CNA
  • russh (crates.io) Vendor— Affected before 0.63.1 Fixed in 0.63.1 Patch available GHSA-47hw-gvq5-r2gm

Remediation

  • Fix · CNA russh (Eugeny) Fixed in 0.63.1
  • Fix · GHSA-47hw-gvq5-r2gm russh (crates.io) Fixed in 0.63.1 Advisory →

Red Hat 1 advisory

  • RHSA-2026:74586 Released 2026-10-01 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images openshell-0.1.2-0.2.hum1@aarch64, openshell-0.1.2-0.2.hum1@src, openshell-0.1.2-0.2.hum1@x86_64 +4

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Hardened ImagesFixed RHSA-2026:74586

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-102823
  2. 2026-10-03 Alias added: GHSA-47hw-gvq5-r2gm

References

Advisory 1

Other 4

  • TI-2026-35550 Russh: SSH message fields were decoded through allocation-first parsers before field-specific bounds CVSS 3.1HIGH 7.5
  • TI-2026-34331 Russh: Post-decompression SSH packet size was not bounded, allowing remote oversized compressed packets CVSS 3.1HIGH 7.5
  • TI-2026-34308 Resource allocation without limits in Eugeny russh CVSS 3.1HIGH 7.5
  • TI-2025-16084 Tabby has a TCC Bypass via Misconfigured Node Fuses CVSS 4.0HIGH 8.6
  • TI-2024-36991 Tabby has a TCC Bypass via Unnecessary Permissive Entitlements in Tabby CVSS 4.0HIGH 8.6
  • TI-2026-82122 Missing confirmation check in russh SSH agent for constrained keys CVSS 4.0HIGH 8.3
See all 25 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences