CVE-2023-6193

Unbounded queuing of path validation messages in cloudflare-quiche

MEDIUM
5.3
CVSS Score
Published: December 12, 2023 at 01:32 PM UTC
Updated: June 17, 2026 at 06:50 AM UTC
1 product affected across 1 vendorQuiche

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.8%

Description

quiche v. 0.15.0 through 0.19.0 was discovered to be vulnerable to unbounded queuing of path validation messages, which could lead to excessive resource consumption. QUIC path validation (RFC 9000 Section 8.2) requires that the recipient of a PATH_CHALLENGE frame responds by sending a PATH_RESPONSE. An unauthenticated remote attacker can exploit the vulnerability by sending PATH_CHALLENGE frames and manipulating the connection (e.g. by restricting the peer's congestion window size) so that PATH_RESPONSE frames can only be sent at the slower rate than they are received; leading to storage of path validation data in an unbounded queue. Quiche versions greater than 0.19.0 address this problem.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

0.15.0 ≤ v ≤ 0.19.00.15.0

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

5.3MEDIUMcloudflare
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
LOW
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-400

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