CVE-2024-2511: OpenSSL · Improperly Controlled Sequential Memory Allocation
Affects OpenSSLSource GCVE Database
Not known to be exploited · CVSS 5.9 Medium.
Data as of 6 Nov 2026, 18:36 UTC
Thin evidence
One scorer or none| CISA-ADP | CVSS 3.1 | 5.9 |
|---|
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 8 Apr 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 6 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| OpenSSL OpenSSL | Affected
| Fixed in– |
AI-suggested
Until a fix is available, avoid using the SSL_OP_NO_TICKET option in TLSv1.3 server configurations without early_data support and default anti-replay protection to prevent triggering the unbounded memory growth. Monitoring and configuration adjustments should be considered to mitigate risk.
Description
CVE-2024-2511 is a vulnerability in OpenSSL TLS servers supporting TLSv1.3 that can cause unbounded memory growth under certain non-default configurations. Specifically, when the SSL_OP_NO_TICKET option is used without early_data support and default anti-replay protection, the session cache may fail to flush properly and grow without limit. This can lead to a denial of service (DoS) condition. The issue does not affect TLS clients, FIPS modules in versions 3.0, 3.1, and 3.2, or OpenSSL 1.0.2.
References
- openssl.org/news/secadv/20240408.txt (opens in a new tab)
- github.com/openssl/openssl/commit/e9d7083e241670332e0443da0f0d4ffb52829f08 (opens in a new tab)
- github.com/openssl/openssl/commit/7e4d731b1c07201ad9374c1cd9ac5263bdf35bce (opens in a new tab)
- github.com/openssl/openssl/commit/b52867a9f618bb955bed2a3ce3db4d4f97ed8e5d (opens in a new tab)
- github.openssl.org/openssl/extended-releases/commit/5f8d25770ae6437db119dfc951e207271a326640 (opens in a new tab)
- openwall.com/lists/oss-security/2024/04/08/5 (opens in a new tab)
- security.netapp.com/advisory/ntap-20240503-0013/ (opens in a new tab)
- lists.debian.org/debian-lts-announce/2024/11/msg00000.html (opens in a new tab)
- lists.debian.org/debian-lts-announce/2024/10/msg00033.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-398330.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-265688.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-354112.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-915275.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-769027.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-613116.html (opens in a new tab)