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Fencer Vulns
medium 5.9

CVE-2024-2511 json

Unbounded memory growth with session handling in TLSv1.3

published 2024-04-08 2 y ago modified 2026-11-06 2 d ago also EUVD-2024-27460 , GHSA-299c-jvhc-gxj8 , JLSEC-2026-249

cvss
5.9
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
59.3%
EPSS 59.3% chance of exploitation in 30 days, percentile 99.1%
public exploits
0
none known

Summary

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.

Patch / fix

  • julia OpenSSL_jll 3.0.15+0
  • julia Openresty_jll 1.27.1+0
  • OpenSSL OpenSSL 1.1.1y, 3.0.14, 3.1.6, 3.2.2
  • Siemens RUGGEDCOM RM1224 LTE(4G) EU V8.2
  • Siemens RUGGEDCOM RM1224 LTE(4G) NAM V8.2
  • Siemens RUGGEDCOM RST2428P V3.1
  • Siemens SCALANCE M804PB V8.2
  • Siemens SCALANCE M812-1 ADSL-Router V8.2
  • Siemens SCALANCE M816-1 ADSL-Router V8.2
  • Siemens SCALANCE M826-2 SHDSL-Router V8.2
  • Siemens SCALANCE M874-2 V8.2
  • Siemens SCALANCE M874-3 V8.2
  • Siemens SCALANCE M874-3 3G-Router (CN) V8.2
  • Siemens SCALANCE M876-3 V8.2
  • Siemens SCALANCE M876-3 (ROK) V8.2
  • Siemens SCALANCE M876-4 V8.2
  • Siemens SCALANCE M876-4 (EU) V8.2
  • Siemens SCALANCE M876-4 (NAM) V8.2
  • Siemens SCALANCE MUM853-1 (A1) V8.2
  • Siemens SCALANCE MUM853-1 (B1) V8.2
  • Siemens SCALANCE MUM853-1 (EU) V8.2
  • Siemens SCALANCE MUM856-1 (A1) V8.2
  • Siemens SCALANCE MUM856-1 (B1) V8.2
  • Siemens SCALANCE MUM856-1 (CN) V8.2
  • Siemens SCALANCE MUM856-1 (EU) V8.2
  • Siemens SCALANCE MUM856-1 (RoW) V8.2
  • Siemens SCALANCE S615 EEC LAN-Router V8.2
  • Siemens SCALANCE S615 LAN-Router V8.2
  • Siemens SCALANCE XCM-/XRM-/XCH-/XRH-300 family V3.1
  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP V3.1.5
  • openssl Debian 12 3.0.14-1~deb12u1
  • openssl Debian 14, Debian 13 3.2.2-1

debian advisories DEBIAN-CVE-2024-2511

  • edk2 Ubuntu 22.04 LTS 2022.02-3ubuntu0.22.04.4
  • edk2 Ubuntu 24.04 LTS 2024.02-2ubuntu0.6
  • openssl Ubuntu 20.04 LTS 1.1.1f-1ubuntu2.23
  • openssl Ubuntu 22.04 LTS 3.0.2-0ubuntu1.17
  • openssl Ubuntu 24.04 LTS 3.0.13-0ubuntu3.2
  • openssl Ubuntu Pro 14.04 LTS 1.0.1f-1ubuntu2.27+esm16
  • openssl Ubuntu Pro 16.04 LTS 1.0.2g-1ubuntu4.20+esm18
  • openssl Ubuntu Pro 18.04 LTS 1.1.1-1ubuntu2.1~18.04.23+esm10

ubuntu advisories UBUNTU-CVE-2024-2511

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • openssl RHEL 9 1:3.2.2-6.el9_5
  • openssl-libs RHEL 9 1:3.2.2-6.el9_5
  • openssl-perl RHEL 9 1:3.2.2-6.el9_5

red hat advisories RHSA-2024:9333

  • libpulp Linux Micro 6.0 0.3.5-1.1
  • openssl-3 Linux Micro 6.0 3.1.4-6.1
  • jitterentropy Linux Micro 6.0 3.4.1-3.1
  • openssl-1_1 SLES for SAP 12 SP5, SLES 12 SP5, SLE Software Development Kit 12 SP5 1.1.1d-2.110.2
  • openssl-1_1 SLES for SAP 15 SP4, SLES 15 SP4-LTSS, SLE Micro 5.4 +7 more 1.1.1l-150400.7.66.2
  • openssl-3 SLES for SAP 15 SP4, SLES 15 SP4-LTSS, SLE Micro 5.4 +7 more 3.0.8-150400.4.54.1
  • openssl-1_1 SLE Module for Basesystem 15 SP5, SLE Micro 5.5, openSUSE Leap 15.5 1.1.1l-150500.17.28.2
  • openssl-3 SLE Module for Basesystem 15 SP5, openSUSE Leap 15.5 3.0.8-150500.5.30.1

suse advisories SUSE-SU-2025:20014-1SUSE-SU-2024:2953-1SUSE-SU-2024:1949-1SUSE-SU-2024:1947-1SUSE-SU-2024:1808-1SUSE-SU-2024:1634-1

  • openssl-1_1 openSUSE Tumbleweed 1.1.1w-9.1
  • openssl-3 openSUSE Tumbleweed 3.1.4-6.1

opensuse advisories openSUSE-SU-2024:13937-1openSUSE-SU-2024:13942-1

  • openssl AlmaLinux 9 1:3.2.2-6.el9_5
  • openssl-libs AlmaLinux 9 1:3.2.2-6.el9_5
  • openssl-perl AlmaLinux 9 1:3.2.2-6.el9_5

almalinux advisories ALSA-2024:9333

  • openssl Rocky Linux 9 1:3.2.2-6.el9_5.1
  • openssl-fips-provider Rocky Linux 9 3.0.7-6.el9_5

rocky linux advisories RLSA-2024:9333

  • openssl Alpine 3.17 3.0.12-r5
  • openssl Alpine 3.19, Alpine 3.18 3.1.4-r6
  • openssl Alpine 3.24, Alpine 3.23, Alpine 3.22 +2 more 3.2.1-r2

alpine advisories ALPINE-CVE-2024-2511

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • openssl Azure Linux 3.0 3.3.0-1
  • nodejs Azure Linux 3.0 20.14.0-1
  • edk2 Azure Linux 3.0 20240524git3e722403cd16-8
  • cloud-hypervisor-cvm CBL-Mariner 2.0, Azure Linux 3.0 38.0.72.2-1
  • openssl CBL-Mariner 2.0 1.1.1k-30
  • hvloader CBL-Mariner 2.0 1.0.1-6

azure linux advisories AZL-39794AZL-39797AZL-40192AZL-42700AZL-42765AZL-42949

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2024-2511 updated cvss 3.7

openssl: Unbounded memory growth with session handling in TLSv1.3

  • Red Hat Enterprise Linux 6 openssl, openssl-perl
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 8 edk2, openssl, edk2-ovmf, edk2-aarch64, openssl-libs, openssl-perl, +1 more Red Hat Enterprise Linux 9 edk2, edk2-ovmf, edk2-tools, edk2-aarch64, compat-openssl11 Red Hat Satellite 6 python-pyOpenSSL, python3-pyOpenSSL, python3.12-pyOpenSSL
    affected: no fix available “Fix deferred”
  • Red Hat Enterprise Linux AppStream (v. 9) openssl-perl 3.2.2-6.el9_5 Red Hat Enterprise Linux BaseOS (v. 9) openssl 3.2.2-6.el9_5, openssl-libs 3.2.2-6.el9_5
    fixed: vendor fix RHSA-2024:9333
  • Red Hat Enterprise Linux 7 openssl, openssl-libs, openssl-perl Red Hat Enterprise Linux 8 shim, shim-x64, shim-aa64, shim-ia32 Red Hat Enterprise Linux 9 shim, shim-x64, shim-aa64 Red Hat Enterprise Linux BaseOS (v. 9) openssl-fips-provider 3.0.7-6.el9_5, openssl-fips-provider-so 3.0.7-6.el9_5
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-24-102-01 updated cvss 3.7

Siemens SIMATIC S7-1500 TM MFP

  • Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
    affected: mitigation, no fix available

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-25-226-15 updated cvss 3.7

Siemens SINEC OS

  • Siemens RUGGEDCOM RST2428P (6GK6242-6PA00) < 3.1 Siemens SCALANCE XCM-/XRM-/XCH-/XRH-300 family < 3.1
    affected: fixed in V3.1 support.industry.siemens.com
  • Siemens SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family
    not affected

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-23-348-10 updated cvss 3.7

Siemens SIMATIC S7-1500

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= 3.1.0, < 3.1.5 Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= 3.1.0, < 3.1.5 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= 3.1.0, < 3.1.5 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) >= 3.1.0, < 3.1.5 Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) >= 3.1.0, < 3.1.5
    affected: fixed in V3.1.5, mitigation support.industry.siemens.com

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-24-319-06 updated cvss 3.7

Siemens SCALANCE M-800 Family

  • Siemens RUGGEDCOM RM1224 LTE(4G) EU (6GK6108-4AM00-2BA2) <V8.2 Siemens RUGGEDCOM RM1224 LTE(4G) NAM (6GK6108-4AM00-2DA2) <V8.2 Siemens SCALANCE M804PB (6GK5804-0AP00-2AA2) <V8.2 Siemens SCALANCE M812-1 ADSL-Router (6GK5812-1AA00-2AA2) <V8.2 Siemens SCALANCE M812-1 ADSL-Router (6GK5812-1BA00-2AA2) <V8.2 Siemens SCALANCE M816-1 ADSL-Router (6GK5816-1AA00-2AA2) <V8.2
    +20 more products
    Siemens SCALANCE M816-1 ADSL-Router (6GK5816-1BA00-2AA2) <V8.2 Siemens SCALANCE M826-2 SHDSL-Router (6GK5826-2AB00-2AB2) <V8.2 Siemens SCALANCE M874-2 (6GK5874-2AA00-2AA2) <V8.2 Siemens SCALANCE M874-3 (6GK5874-3AA00-2AA2) <V8.2 Siemens SCALANCE M874-3 3G-Router (CN) (6GK5874-3AA00-2FA2) <V8.2 Siemens SCALANCE M876-3 (6GK5876-3AA02-2BA2) <V8.2 Siemens SCALANCE M876-3 (ROK) (6GK5876-3AA02-2EA2) <V8.2 Siemens SCALANCE M876-4 (6GK5876-4AA10-2BA2) <V8.2 Siemens SCALANCE M876-4 (EU) (6GK5876-4AA00-2BA2) <V8.2 Siemens SCALANCE M876-4 (NAM) (6GK5876-4AA00-2DA2) <V8.2 Siemens SCALANCE MUM853-1 (A1) (6GK5853-2EA10-2AA1) <V8.2 Siemens SCALANCE MUM853-1 (B1) (6GK5853-2EA10-2BA1) <V8.2 Siemens SCALANCE MUM853-1 (EU) (6GK5853-2EA00-2DA1) <V8.2 Siemens SCALANCE MUM856-1 (A1) (6GK5856-2EA10-3AA1) <V8.2 Siemens SCALANCE MUM856-1 (B1) (6GK5856-2EA10-3BA1) <V8.2 Siemens SCALANCE MUM856-1 (CN) (6GK5856-2EA00-3FA1) <V8.2 Siemens SCALANCE MUM856-1 (EU) (6GK5856-2EA00-3DA1) <V8.2 Siemens SCALANCE MUM856-1 (RoW) (6GK5856-2EA00-3AA1) <V8.2 Siemens SCALANCE S615 EEC LAN-Router (6GK5615-0AA01-2AA2) <V8.2 Siemens SCALANCE S615 LAN-Router (6GK5615-0AA00-2AA2) <V8.2
    affected: fixed in V8.2 support.industry.siemens.com

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-25-044-09 updated cvss 3.7

Siemens SCALANCE W700 IEEE 802.11ax

  • Siemens SCALANCE WAB762-1 (6GK5762-1AJ00-6AA0) <V3.0.0 Siemens SCALANCE WAM763-1 (6GK5763-1AL00-7DA0) <V3.0.0 Siemens SCALANCE WAM763-1 (ME) (6GK5763-1AL00-7DC0) <V3.0.0 Siemens SCALANCE WAM763-1 (US) (6GK5763-1AL00-7DB0) <V3.0.0 Siemens SCALANCE WAM766-1 (6GK5766-1GE00-7DA0) <V3.0.0 Siemens SCALANCE WAM766-1 (ME) (6GK5766-1GE00-7DC0) <V3.0.0
    +13 more products
    Siemens SCALANCE WAM766-1 (US) (6GK5766-1GE00-7DB0) <V3.0.0 Siemens SCALANCE WAM766-1 EEC (6GK5766-1GE00-7TA0) <V3.0.0 Siemens SCALANCE WAM766-1 EEC (ME) (6GK5766-1GE00-7TC0) <V3.0.0 Siemens SCALANCE WAM766-1 EEC (US) (6GK5766-1GE00-7TB0) <V3.0.0 Siemens SCALANCE WUB762-1 (6GK5762-1AJ00-1AA0) <V3.0.0 Siemens SCALANCE WUB762-1 iFeatures (6GK5762-1AJ00-2AA0) <V3.0.0 Siemens SCALANCE WUM763-1 (6GK5763-1AL00-3AA0) <V3.0.0 Siemens SCALANCE WUM763-1 (6GK5763-1AL00-3DA0) <V3.0.0 Siemens SCALANCE WUM763-1 (US) (6GK5763-1AL00-3AB0) <V3.0.0 Siemens SCALANCE WUM763-1 (US) (6GK5763-1AL00-3DB0) <V3.0.0 Siemens SCALANCE WUM766-1 (6GK5766-1GE00-3DA0) <V3.0.0 Siemens SCALANCE WUM766-1 (ME) (6GK5766-1GE00-3DC0) <V3.0.0 Siemens SCALANCE WUM766-1 (USA) (6GK5766-1GE00-3DB0) <V3.0.0
    affected: fixed in V3.0.0 support.industry.siemens.com

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 y ago

Exploit prediction

59.30% chance of exploitation in the next 30 days, higher than 99.1% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
OSV 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
julia OpenSSL_jll
<3.0.15+0
3.0.15+0
julia Openresty_jll
<1.27.1+0
1.27.1+0

Affected products

  • OpenSSL OpenSSL
  • Siemens RUGGEDCOM RM1224 LTE(4G) EU
  • Siemens RUGGEDCOM RM1224 LTE(4G) NAM
  • Siemens RUGGEDCOM RST2428P
  • Siemens SCALANCE M804PB
  • Siemens SCALANCE M812-1 ADSL-Router
  • Siemens SCALANCE M816-1 ADSL-Router
  • Siemens SCALANCE M826-2 SHDSL-Router
  • Siemens SCALANCE M874-2
  • Siemens SCALANCE M874-3
  • Siemens SCALANCE M874-3 3G-Router (CN)
  • Siemens SCALANCE M876-3
  • Siemens SCALANCE M876-3 (ROK)
  • Siemens SCALANCE M876-4
  • Siemens SCALANCE M876-4 (EU)
  • Siemens SCALANCE M876-4 (NAM)
  • Siemens SCALANCE MUM853-1 (A1)
  • Siemens SCALANCE MUM853-1 (B1)
  • Siemens SCALANCE MUM853-1 (EU)
  • Siemens SCALANCE MUM856-1 (A1)
  • Siemens SCALANCE MUM856-1 (B1)
  • Siemens SCALANCE MUM856-1 (CN)
  • Siemens SCALANCE MUM856-1 (EU)
  • Siemens SCALANCE MUM856-1 (RoW)
  • Siemens SCALANCE S615 EEC LAN-Router
  • Siemens SCALANCE S615 LAN-Router
  • Siemens SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family
  • Siemens SCALANCE XCM-/XRM-/XCH-/XRH-300 family
  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
  • Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
  • Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
  • Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

Classification

Weakness
  • CWE-1325 Improperly Controlled Sequential Memory Allocation
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.