CVE-2026-12707 (GCVE-0-2026-12707)
Vulnerability from cvelistv5 – Published: 2026-07-14 15:18 – Updated: 2026-07-14 15:57
VLAI
EPSS
VEX
Title
Unbounded path event queue growth in quiche via peer-driven source connection ID rotation
Summary
Summary
Cloudflare quiche was discovered to be vulnerable to memory resource exhaustion due to unbounded queuing of post-handshake client migration events.
Impact
quiche supports the connection migration features described in Section 9 of RFC 9000, which allows a single QUIC connection to survive changes in the network path. Although quiche implements the protections described in Section 9.3 of RFC 9000 to limit server state commitment, it was discovered that the collection of PathEvents, intended to be consumed by applications via the path_event_next() function, was not bounded.
Once the QUIC handshake completed, a peer could exploit rapid source address migration in order to cause unbounded queuing of the PathEvent::ReusedSourceConnectionId type. Servers are vulnerable even if active connection migration is disabled.
Mitigation:
*
Applications can call path_event_next() to drain the PathEvent collection, mitigating the attack.
*
Users are requested to upgrade to quiche 0.29.3 which is the earliest version that prevents excessive queueing of PathEvent::ReusedSourceConnectionId.
Severity
7.5 (High)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-14 15:57 UTC
CWE
- CWE-770 - Allocation of resources without limits or throttling
Assigner
References
1 reference
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Cloudflare | quiche |
Affected:
0.15.0 , < 0.29.3
(semver)
|
guessed |
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