CVE-2024-2511

MEDIUMCVSS 5.9/10EPSS 54.03%

Last modified

CVE-2024-2511 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. 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. EPSS estimates a 54.03% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1
5.9/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability
54.03%

98.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

References

Timeline

Published
Last Modified
Status
Deferred

Frequently Asked Questions

What is 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 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.
How severe is CVE-2024-2511?
CVE-2024-2511 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 54.03% probability of exploitation in the next 30 days.
How do I fix CVE-2024-2511?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2024-2511?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST