CVE-2025-7054: Infinite loop triggered by connection ID retirement
Impact
Cloudflare quiche was discovered to be vulnerable to an infinite loop when sending packets containing RETIRECONNECTIONID frames.
QUIC connections possess a set of connection identifiers (IDs); see Section 5.1 of RFC 9000. Once the QUIC handshake completes, a local endpoint is responsible for issuing and retiring Connection IDs that are used by the remote peer to populate the Destination Connection ID field in packets sent from remote to local. Each Connection ID has a sequence number to ensure synchronization between peers
An unauthenticated remote attacker can exploit this vulnerability by first completing a handshake and then sending a specially-crafted set of frames that trigger a connection ID retirement in the victim. When the victim attempts to send a packet containing RETIRECONNECTIONID frames, Section 19.16 of RFC 9000 requires that the sequence number of the retired connection ID must not be the same as the sequence number of the connection ID used by the packet. In other words, a packet cannot contain a frame that retires itself. In scenarios such as path migration, it is possible for there to be multiple active paths with different active connection IDs that could be used to retire each other. The exploit triggered an unintentional behaviour of a quiche design feature that supports retirement across paths while maintaining full connection ID synchronization, leading to an infinite loop.
Patches
quiche 0.24.5 is the earliest version containing the fix for the issue
Other sources
Cloudflare quiche was discovered to be vulnerable to an infinite loop when sending packets containing RETIRECONNECTIONID frames.
QUIC connections possess a set of connection identifiers (IDs); see Section 5.1 of RFC 9000 https://datatracker.ietf.org/doc/html/rfc9000#section-5.1 . Once the QUIC handshake completes, a local endpoint is responsible for issuing and retiring Connection IDs that are used by the remote peer to populate the Destination Connection ID field in packets sent from remote to local. Each Connection ID has a sequence number to ensure synchronization between peers.
An unauthenticated remote attacker can exploit this vulnerability by first completing a handshake and then sending a specially-crafted set of frames that trigger a connection ID retirement in the victim. When the victim attempts to send a packet containing RETIRECONNECTIONID frames, Section 19.16 of RFC 9000 https://datatracker.ietf.org/doc/html/rfc9000#section-19.6 requires that the sequence number of the retired connection ID must not be the same as the sequence number of the connection ID used by the packet. In other words, a packet cannot contain a frame that retires itself. In scenarios such as path migration, it is possible for there to be multiple active paths with different active connection IDs that could be used to retire each other. The exploit triggered an unintentional behaviour of a quiche design feature that supports retirement across paths while maintaining full connection ID synchronization, leading to an infinite loop.This issue affects quiche: from 0.15.0 before 0.24.5.
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
rust/quicheto a version that resolves this vulnerability.Fixed in 0.24.5 - Upgrade
Upgrade
Cloudflare quicheto a version that resolves this vulnerability.Fixed in 0.24.5
Event History
Frequently Asked Questions
What is the severity of CVE-2025-7054?
CVE-2025-7054 is classified as a high severity vulnerability due to its potential to cause an infinite loop in Cloudflare quiche.
How do I fix CVE-2025-7054?
To fix CVE-2025-7054, you should update to the latest version of Cloudflare quiche that contains the patch for this vulnerability.
What are the implications of CVE-2025-7054 for my application?
The implications of CVE-2025-7054 include potential application downtime or degraded performance due to an infinite loop when handling specific packets.
Which software is affected by CVE-2025-7054?
CVE-2025-7054 affects the Cloudflare quiche implementation, specifically those utilizing RETIRE_CONNECTION_ID frames.
Is there a workaround for CVE-2025-7054 until I can apply a fix?
As a workaround for CVE-2025-7054, it is advisable to avoid using the affected packet types until the vulnerability can be patched.