What is CVE-2026-10740?

CVE-2026-10740 is a medium-severity vulnerability in AWS S2n-Quic, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 5.3/10. Published 2026-06-10.

How severe is CVE-2026-10740?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Resource exhaustion in AWS S2n-Quic

CVE-2026-10740

Unbounded memory allocation in the CRYPTO frame reassembler in s2n-quic before 1.8.2 may allow an unauthenticated remote actor to cause a denial of service (degraded availability) by sending crafted QUIC Initial packets. To remediate this issue, users should upgrade to v1.8.2.

Published 2026-06-10 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.003 (22.0th percentile), scored 2026-09-23.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 22nd percentile — 22.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

AWS S2n-Quic — versions 0

Weakness classification (CWE)

CWE-770 — Allocation of Resources Without Limits or Throttling

References

ff89ba41-3aa1-4d27-914a-91399e9639e5 (vendor-advisory)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (patch)
ff89ba41-3aa1-4d27-914a-91399e9639e5 (third-party-advisory)

Frequently asked questions

What is CVE-2026-10740?: CVE-2026-10740 is a medium-severity vulnerability in AWS S2n-Quic, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 5.3/10. Published 2026-06-10.
How severe is CVE-2026-10740?: Medium severity. CVSS v3 base score is 5.3 out of 10.