New QPACK Flaws Can Crash HTTP/3 Servers, Trigger Up to 4,000-Fold Memory Amplification

A remote attacker who has not logged in can crash many HTTP/3 web servers with a single connection, security firm FoxIO disclosed, releasing working proof-of-concept code. By sending a small batch of compressed HTTP headers that expands in memory to a much larger set, the attacker can force the...

CVE-2026-12523

Summary Cloudflare quiche's HTTP/3 layer was discovered to be vulnerable to resource exhaustion i.e., memory by means of specially crafted HTTP/3 frames. Impact HTTP/3 defines multiple frame types to support HTTP message exchanges and connection management. Each frame has a length and a payload...

CVE-2026-12707

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...

EUVD-2026-43748

Summary Cloudflare quiche's HTTP/3 layer was discovered to be vulnerable to resource exhaustion i.e., memory by means of specially crafted HTTP/3 frames. Impact HTTP/3 defines multiple frame types to support HTTP message exchanges and connection management. Each frame has a length and a payload...

CVE-2026-12523 Resource exhaustion in quiche HTTP/3 and QPACK layers

Summary Cloudflare quiche's HTTP/3 layer was discovered to be vulnerable to resource exhaustion i.e., memory by means of specially crafted HTTP/3 frames. Impact HTTP/3 defines multiple frame types to support HTTP message exchanges and connection management. Each frame has a length and a payload...

CVE-2026-12523 Resource exhaustion in quiche HTTP/3 and QPACK layers

Summary Cloudflare quiche's HTTP/3 layer was discovered to be vulnerable to resource exhaustion i.e., memory by means of specially crafted HTTP/3 frames. Impact HTTP/3 defines multiple frame types to support HTTP message exchanges and connection management. Each frame has a length and a payload...

CVE-2026-12523

Summary Cloudflare quiche's HTTP/3 layer was discovered to be vulnerable to resource exhaustion i.e., memory by means of specially crafted HTTP/3 frames. Impact HTTP/3 defines multiple frame types to support HTTP message exchanges and connection management. Each frame has a length and a payload...

CVE-2026-12707

CVE-2026-12707 affects Cloudflare quiche. After QUIC handshakes, an attacker can trigger unbounded queuing of PathEvent::ReusedSourceConnectionId during rapid source address migration, causing memory resource exhaustion. Affected component is quiche’s PathEvents collection (path_event_next() drai...

EUVD-2026-43716

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...

CVE-2026-12707 Unbounded path event queue growth in quiche via peer-driven source connection ID rotation

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...

CVE-2026-12707 Unbounded path event queue growth in quiche via peer-driven source connection ID rotation

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...

CVE-2026-12707

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...

CVE-2026-12707 Unbounded path event queue growth in quiche via peer-driven source connection ID rotation

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...

PT-2026-58061

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...

CVE-2026-12707: Allocation of Resources Without Limits or Throttling

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...

CVE-2026-12523: Uncontrolled Resource Consumption

Summary Cloudflare quiche's HTTP/3 layer was discovered to be vulnerable to resource exhaustion i.e., memory by means of specially crafted HTTP/3 frames. Impact HTTP/3 defines multiple frame types to support HTTP message exchanges and connection management. Each frame has a length and a payload...

PT-2026-58086

Name of the Vulnerable Software and Affected Versions quiche versions prior to 0.29.3 Description The HTTP/3 layer is susceptible to memory resource exhaustion through the use of specially crafted HTTP/3 frames. The issue occurs during the parsing of certain frame types where memory is...

futures-quic (>=0.2.4, <=0.2.8), n3quic (>=0.1.1, <=0.1.6) +6 more potentially affected by CVE-2026-11941 via quiche (>=0.20.1, <=0.24.9)

quiche CARGO version =0.20.1, =0.2.4, =0.1.1, =0.1.0, =0.1.19, =0.1.19, =0.1.19, =0.1.19, =0.1.21 Source cves: CVE-2026-11941 Source advisory: OSV:GHSA-MH64-PH39-MRC9...

EUVD-2026-38003

Cloudflare Quiche: Use-after-free in connection ID iterator FFI functions...

Cloudflare Quiche: Use-after-free in connection ID iterator FFI functions

Impact Cloudflare Quiche was affected by 2 use-after-free vulnerabilities in the connection ID iterator FFI functions. The quicheconnectioniditernext and quicheconnretiredscidnext functions would return a pointer to a ConnectionId to the applications via function arguments, but the the owned...