CVE-2026-34183
Issue summary: Remote peer may exhaust heap memory of the QUIC server or client by flooding it with packets containing PATH_CHALLENGE frames.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.05%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Issue summary: Remote peer may exhaust heap memory of the QUIC server or client by flooding it with packets containing PATH_CHALLENGE frames. Impact summary: A malicious remote peer can cause an unbounded memory allocation which can lead to an abnormal termination of the application acting as a QUIC client or server and a Denial of Service. A remote peer may exhaust heap memory by flooding the local QUIC stack with PATH_CHALLENGE frames. The local QUIC stack allocates a PATH_RESPONSE frame for every PATH_CHALLENGE it receives. The allocated PATH_RESPONSE frame gets freed only when the remote peer acknowledges reception of the PATH_RESPONSE frame which will not be done by a malicious peer. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue. The QUIC stack is outside of OpenSSL FIPS module boundary.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.05% probability · 62th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-1325
- Affected
- openssl/openssl
- Source
- openssl-security@openssl.org
References
- https://github.com/openssl/openssl/commit/5b306efb0b3779dfdd0803b4afc9d08c91f11517Patch
- https://github.com/openssl/openssl/commit/7d06955ebe0ecf8adfd4c1e92018586da47ef9acPatch
- https://github.com/openssl/openssl/commit/d2e9efbe4900a373227deb136e8665401404ffacPatch
- https://github.com/openssl/openssl/commit/fbaa83859c01ad64f497b757aaf51be7d05ed9ebPatch
- https://openssl-library.org/news/secadv/20260609.txtVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.