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.

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.

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.

EDK II is a modern, feature-rich, cross-platform firmware development environment for the UEFI and PI specifications.

Security Fix(es):

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.(CVE-2024-2511)

The OpenSSL Project is a collaborative effort to develop a robust, commercial-grade, fully featured, and Open Source toolkit implementing the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1) protocols as well as a full-strength general purpose cryptography library. The project is managed by a worldwide community of volunteers that use the Internet to communicate, plan, and develop the OpenSSL tookit and its related documentation.

Security Fix(es):

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.(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.

OpenSSL is a toolkit that implements the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) protocols, as well as a full-strength general-purpose cryptography library.

Security Fix(es):

• openssl: Unbounded memory growth with session handling in TLSv1.3 (CVE-2024-2511)
• openssl: Excessive time spent checking DSA keys and parameters (CVE-2024-4603)
• openssl: Use After Free with SSL_free_buffers (CVE-2024-4741)
• openssl: SSL_select_next_proto buffer overread (CVE-2024-5535)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the AlmaLinux Release Notes linked from the References section.

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.

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.

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.

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.

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.

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.

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.

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.

• CVE-2024-2511: Fix an issue where some non-default TLS server configurations can cause unbounded memory growth when processing TLSv1.3 sessions

• CVE-2024-2511: unbounded TLSv1.3 session-cache growth via not_resumable session duplication; cache full handshakes only and clear not_resumable on dup so the entry remains evictable

Unbounded memory growth with session handling in TLSv1.3. (CVE-2024-2511)

The updated packages fix security vulnerabilities

These are all security issues fixed in the libopenssl-1_1-devel-1.1.1w-9.1 package on the GA media of openSUSE Tumbleweed.

These are all security issues fixed in the libopenssl-3-devel-3.1.4-6.1 package on the GA media of openSUSE Tumbleweed.

OpenSSL is a toolkit that implements the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) protocols, as well as a full-strength general-purpose cryptography library.

Security Fix(es):

• openssl: Unbounded memory growth with session handling in TLSv1.3 (CVE-2024-2511)

• openssl: Excessive time spent checking DSA keys and parameters (CVE-2024-4603)

• openssl: Use After Free with SSL_free_buffers (CVE-2024-4741)

• openssl: SSL_select_next_proto buffer overread (CVE-2024-5535)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the Rocky Linux 9.5 Release Notes linked from the References section.

This update for openssl-1_1 fixes the following issues:

• CVE-2024-2511: Fixed unconstrained session cache growth in TLSv1.3 (bsc#1222548).

This update for openssl-3 fixes the following issues:

• CVE-2024-2511: Fixed unconstrained session cache growth in TLSv1.3 (bsc#1222548).

This update for openssl-1_1 fixes the following issues:

• CVE-2024-2511: Fixed unconstrained session cache growth in TLSv1.3 (bsc#1222548).

This update for openssl-3 fixes the following issues:

• CVE-2024-2511: Fixed unconstrained session cache growth in TLSv1.3 (bsc#1222548).
• CVE-2024-4603: Fixed DSA parameter checks for excessive sizes before validating (bsc#1224388).

This update for openssl-1_1 fixes the following issues:

• CVE-2024-2511: Fixed unconstrained session cache growth in TLSv1.3 (bsc#1222548).

This update for openssl-1_1 fixes the following issues:

• CVE-2024-2511: Fixed a denial of service due to unbounded memory growth with session handling in TLSv1.3 (bsc#1222548)
• CVE-2024-5535: Fixed a buffer overread in function SSL_select_next_proto() with an empty supported client protocols buffer (bsc#1227138)

This update for openssl-3, libpulp, ulp-macros fixes the following issues:

openssl-3:

• CVE-2024-6119: possible denial of service in X.509 name checks (bsc#1229465)
• CVE-2024-5535: SSL_select_next_proto buffer overread (bsc#1227138)
• CVE-2024-4741: Fixed a use-after-free with SSL_free_buffers (bsc#1225551)
• CVE-2024-4603: Check DSA parameters for excessive sizes before validating (bsc#1224388)
• CVE-2024-2511: Fix unconstrained session cache growth in TLSv1.3 (bsc#1222548)
• FIPS: Deny SHA-1 signature verification in FIPS provider (bsc#1221365)
• FIPS: RSA keygen PCT requirements. (bsc#1221760, bsc#1221753)
• FIPS: Check that the fips provider is available before setting it as the default provider in FIPS mode. (bsc#1220523)
• FIPS: Port openssl to use jitterentropy (bsc#1220523)
• FIPS: Block non-Approved Elliptic Curves (bsc#1221786)
• FIPS: Service Level Indicator (bsc#1221365)
• FIPS: Output the FIPS-validation name and module version which uniquely identify the FIPS validated module. (bsc#1221751)
• FIPS: Add required selftests (bsc#1221760)
• FIPS: DH: Disable FIPS 186-4 Domain Parameters (bsc#1221821)
• FIPS: Recommendation for Password-Based Key Derivation (bsc#1221827)
• FIPS: Zeroization is required (bsc#1221752)
• FIPS: Reseed DRBG (bsc#1220690, bsc#1220693, bsc#1220696)
• FIPS: NIST SP 800-56Brev2 (bsc#1221824)
• FIPS: Approved Modulus Sizes for RSA Digital Signature for FIPS 186-4 (bsc#1221787)
• FIPS: Port openssl to use jitterentropy (bsc#1220523)
• FIPS: NIST SP 800-56Arev3 (bsc#1221822)
• FIPS: Error state has to be enforced (bsc#1221753)
• Build with enabled sm2 and sm4 support (bsc#1222899)
• fix non-reproducible build issue
• Fix HDKF key derivation (bsc#1225291)
• Enable livepatching support (bsc#1223428)

libpulp:

• Update package with libpulp-0.3.5

  • Change .so load policy from lazy to eager.
  • Fix patch of references when mprotect is enabled.
  • Fix tramposed calloc arguments.
  • Fix crash of ulp packer on empty lines.

• Disabled ptrace_scope through aaa_base-enable-ptrace package (bsc#1221763).

• Update package with libpulp-0.3.4:

  • Add debuginfo into ulp extract.

• Disabled ptrace_scope when building the package (bsc#1221763).

• Update package with libpulp-0.3.3:

  • Fixed a race condition when process list is empty.
  • Removed "Unable to get section data" error message (bsc#1223306).
  • Bumped asunsafe_conversion attempts from 100 to 2000.
  • Fixed banner test on clang-18.
  • Check if ptrace_scope is enabled when attempting a ptrace operation (bsc#1221763).

• Update package with libpulp-0.3.1:

  • Add timestamp information on ulp patches.

ulp-macros:

• Initial release.

It was discovered that OpenSSL incorrectly handled TLSv1.3 sessions when certain non-default TLS server configurations were in use. A remote attacker could possibly use this issue to cause OpenSSL to consume resources, leading to a denial of service. (CVE-2024-2511)

It was discovered that OpenSSL incorrectly handled checking excessively long DSA keys or parameters. A remote attacker could possibly use this issue to cause OpenSSL to consume resources, leading to a denial of service. This issue only affected Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2024-4603)

William Ahern discovered that OpenSSL incorrectly handled certain memory operations in a rarely-used API. A remote attacker could use this issue to cause OpenSSL to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2024-4741)

Joseph Birr-Pixton discovered that OpenSSL incorrectly handled calling a certain API with an empty supported client protocols buffer. A remote attacker could possibly use this issue to obtain sensitive information, or cause OpenSSL to crash, resulting in a denial of service. (CVE-2024-5535)

It was discovered that EDK II was susceptible to a predictable TCP Initial Sequence Number. An attacker could possibly use this issue to gain unauthorized access. This issue only affected Ubuntu 22.04 LTS, and Ubuntu 24.04 LTS. (CVE-2023-45236, CVE-2023-45237)

It was discovered that EDK II incorrectly handled S3 sleep. An attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 22.04 LTS, and Ubuntu 24.04 LTS. (CVE-2024-1298)

It was discovered that the EDK II PE/COFF loader incorrectly handled certain memory operations. An attacker could possibly use this issue to cause a denial of service, obtain sensitive information, or execute arbitrary code. This issue only affected Ubuntu 22.04 LTS, and Ubuntu 24.04 LTS. (CVE-2024-38796)

It was discovered that the EDK II PE image hashing function incorrectly handled certain memory operations. An attacker could possibly use this issue to cause a denial of service, or execute arbitrary code. (CVE-2024-38797)

It was discovered that the EDK II BIOS incorrectly handled certain memory operations. An attacker could possibly use this issue to cause a denial of service. (CVE-2024-38805, CVE-2025-2295)

It was discovered that EDK II incorrectly handled the enabling of MCE. An attacker could possibly use this issue to cause a denial of service, or execute arbitrary code. (CVE-2025-3770)

It was discovered that the OpenSSL library embedded in EDK II contained multiple vulnerabilties. An attacker could possibly use these issues to cause a denial of service, obtain sensitive information, or execute arbitrary code. (CVE-2021-3712, CVE-2022-0778, CVE-2022-4304, CVE-2022-4450, CVE-2023-0215, CVE-2023-0286, CVE-2023-0464, CVE-2023-0465, CVE-2023-0466, CVE-2023-2650, CVE-2023-3446, CVE-2023-3817, CVE-2023-5678, CVE-2023-6237, CVE-2024-0727, CVE-2024-13176, CVE-2024-2511, CVE-2024-41996, CVE-2024-4741, CVE-2024-5535, CVE-2024-6119, CVE-2024-9143, CVE-2025-9232)

USN-8678-1 fixed vulnerabilities in OpenSSL. This update provides the corresponding fix for OpenSSL and OpenSSL 1.0 on Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, and Ubuntu 18.04 LTS.

In addition, this update also fixes the following issues that were not previously addressed in those releases:

It was discovered that OpenSSL incorrectly handled TLS handshake message buffering. A remote attacker could possibly use this issue to cause OpenSSL to consume excessive memory, leading to a denial of service. (LP: #2161371)

It was discovered that OpenSSL incorrectly handled session cache management when processing TLSv1.3 sessions. A remote attacker could possibly use this issue to cause OpenSSL to consume excessive memory, leading to a denial of service. This issue only affected OpenSSL 1.1.1 on Ubuntu 18.04 LTS. (CVE-2024-2511)

It was discovered that OpenSSL incorrectly handled the SSL_select_next_proto function when called with an empty client protocol list. A remote attacker could possibly use this issue to cause OpenSSL to disclose private memory contents to the peer, leading to a loss of confidentiality. This issue only affected Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. (CVE-2024-5535)

Original advisory details:

It was discovered that OpenSSL incorrectly handled buffering of DTLS records for a future epoch. A remote attacker could possibly use this issue to cause OpenSSL to use excessive resources, leading to a denial of service. (CVE-2026-54874)

It was discovered that OpenSSL incorrectly handled CMS key unwrapping. A remote attacker could possibly use this issue to cause a heap buffer overflow, leading to a denial of service or arbitrary code execution. (CVE-2026-63072)