CVE-2024-2511
Issue summary: Some non-default TLS server configurations can cause unbounded memory growth when processing TLSv1.3 sessions Impact summary: An attacker may exploit certain server configurations to trigger unbounded memory growth that would lead to a…
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 52.4%, higher than 99% of all known CVEs. Patch or mitigate before the next change window.
Description
Issue summary: Some non-default TLS server configurations can cause unbounded memory growth when processing TLSv1.3 sessions Impact summary: An attacker may exploit certain server configurations to trigger unbounded memory growth that would lead to a Denial of Service This problem can occur in TLSv1.3 if the non-default SSL_OP_NO_TICKET option is being used (but not if early_data support is also configured and the default anti-replay protection is in use). In this case, under certain conditions, the session cache can get into an incorrect state and it will fail to flush properly as it fills. The session cache will continue to grow in an unbounded manner. A malicious client could deliberately create the scenario for this failure to force a Denial of Service. It may also happen by accident in normal operation. This issue only affects TLS servers supporting TLSv1.3. It does not affect TLS clients. The FIPS modules in 3.2, 3.1 and 3.0 are not affected by this issue. OpenSSL 1.0.2 is also not affected by this issue.
- CVSS 3.1
- 5.9 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 52.42% probability · 99th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-1325
- Source
- openssl-security@openssl.org
EPSS moved from 52.4% on 24 September 2026 to 52.4% on 3 November 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
References
- https://github.com/openssl/openssl/commit/7e4d731b1c07201ad9374c1cd9ac5263bdf35bce
- https://github.com/openssl/openssl/commit/b52867a9f618bb955bed2a3ce3db4d4f97ed8e5d
- https://github.com/openssl/openssl/commit/e9d7083e241670332e0443da0f0d4ffb52829f08
- https://github.openssl.org/openssl/extended-releases/commit/5f8d25770ae6437db119dfc951e207271a326640
- https://www.openssl.org/news/secadv/20240408.txt
- http://www.openwall.com/lists/oss-security/2024/04/08/5
- https://github.com/openssl/openssl/commit/7e4d731b1c07201ad9374c1cd9ac5263bdf35bce
- https://github.com/openssl/openssl/commit/b52867a9f618bb955bed2a3ce3db4d4f97ed8e5d
- https://github.com/openssl/openssl/commit/e9d7083e241670332e0443da0f0d4ffb52829f08
- https://github.openssl.org/openssl/extended-releases/commit/5f8d25770ae6437db119dfc951e207271a326640
- https://lists.debian.org/debian-lts-announce/2024/10/msg00033.html
- https://lists.debian.org/debian-lts-announce/2024/11/msg00000.html
- https://security.netapp.com/advisory/ntap-20240503-0013/
- https://www.openssl.org/news/secadv/20240408.txt
- https://cert-portal.siemens.com/productcert/html/ssa-265688.html
- https://cert-portal.siemens.com/productcert/html/ssa-354112.html
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html
- https://cert-portal.siemens.com/productcert/html/ssa-613116.html
- https://cert-portal.siemens.com/productcert/html/ssa-769027.html
- https://cert-portal.siemens.com/productcert/html/ssa-915275.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.