CVE-2026-63075EPSS p54.3%
CVE-2026-63075CVE-2026-63075
openssl / openssl
Description
Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly
sends ack-eliciting packets while not acknowledging ACK-only responses, the
QUIC stack can retain ACK-only packet metadata for the lifetime of the
connection.
Impact summary: A remote peer that can complete a QUIC handshake can
cause connection-scoped memory growth which may lead to Denial of Service
through memory exhaustion, especially with sustained traffic or many concurrent
QUIC connections.
CWE: CWE-770: Allocation of Resources Without Limits or Throttling
Description: When the OpenSSL QUIC stack sends an ACK-only packet,
there is no requirement by the QUIC protocol that the peer will acknowledge
that ACK-only packet (i.e. it is itself not ack-eliciting). However, the OpenSSL
implementation stores the metadata about the ACK frames regardless.
In and of itself that's ok, but if a malicious peer establishes a connection, and
then drives the connection such that ACK-only packets are forced from the
Op
Scoring
| CVSS | 7.5 () |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| EPSS | 0.78% probability of exploitation · percentile 54.3% · 2026-10-05T12:00:23Z |
| Last modified | 2026-09-11 |