Gnutls: gnutls: denial of service via heap buffer overflow in dtls handshake fragment reassembly
Summary
| CVE | CVE-2026-33846 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-04 10:15:59 UTC |
| Updated | 2026-09-04 13:19:06 UTC |
| Description | A heap buffer overflow vulnerability exists in the DTLS handshake fragment reassembly logic of GnuTLS. The issue arises in merge_handshake_packet() where incoming handshake fragments are matched and merged based solely on handshake type, without validating that the message_length field remains consistent across all fragments of the same logical message. An attacker can exploit this by sending crafted DTLS fragments with conflicting message_length values, causing the implementation to allocate a buffer based on a smaller initial fragment and subsequently write beyond its bounds using larger, inconsistent fragments. Because the merge operation does not enforce proper bounds checking against the allocated buffer size, this results in an out-of-bounds write on the heap. The vulnerability is remotely exploitable without authentication via the DTLS handshake path and can lead to application crashes or potential memory corruption. |
Risk And Classification
Primary CVSS: v3.1 7.5 HIGH from ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.012630000 probability, percentile 0.677650000 (date 2026-09-07)
Problem Types: CWE-130 | CWE-130 Improper Handling of Length Parameter Inconsistency
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | CVSS | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | [email protected] | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | CVSS | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Red Hat | Red Hat Enterprise Linux 10 | unaffected 0:3.8.10-4.el10_2 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | unaffected 0:3.8.9-9.el10_0.19 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 7 Extended Lifecycle Support | unaffected 0:3.3.29-9.el7_9.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8 | unaffected 0:3.6.16-8.el8_10.6 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8 | unaffected 0:3.6.16-8.el8_10.6 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | unaffected 0:3.6.14-10.el8_4.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | unaffected 0:4.13-3.el8_4.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | unaffected 0:3.6.14-10.el8_4.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | unaffected 0:4.13-3.el8_4.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | unaffected 0:3.6.16-5.el8_6.5 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | unaffected 0:4.13-3.el8_6.2 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | unaffected 0:3.6.16-5.el8_6.5 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | unaffected 0:4.13-3.el8_6.2 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | unaffected 0:3.6.16-7.el8_8.4 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | unaffected 0:4.13-4.el8_8.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.8 Update Services For SAP Solutions | unaffected 0:3.6.16-7.el8_8.4 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8.8 Update Services For SAP Solutions | unaffected 0:4.13-4.el8_8.1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9 | unaffected 0:3.8.10-4.el9_8 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9 | unaffected 0:3.8.10-4.el9_8 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9.2 Update Services For SAP Solutions | unaffected 0:3.7.6-21.el9_2.7 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9.4 Update Services For SAP Solutions | unaffected 0:3.8.3-4.el9_4.6 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | unaffected 0:3.8.3-6.el9_6.4 * rpm | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4.12 | unaffected 412.86.202608241157-0 * rpm | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4.14 | unaffected 414.92.202608172040-0 * rpm | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4.15 | unaffected 415.92.202608180329-0 * rpm | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4.16 | unaffected 416.94.202608150307-0 * rpm | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4.17 | unaffected 417.94.202608250221-0 * rpm | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4.18 | unaffected 418.94.202608142238-0 * rpm | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4.19 | unaffected 4.19.9.6.202608182320-0 * rpm | Not specified |
| CNA | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951051 * rpm | Not specified |
| CNA | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951012 * rpm | Not specified |
| CNA | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951244 * rpm | Not specified |
| CNA | Red Hat | Red Hat Discovery 2 | unaffected 1782159791 * rpm | Not specified |
| CNA | Red Hat | Red Hat Discovery 2 | unaffected 1782166952 * rpm | Not specified |
| CNA | Red Hat | Red Hat Hardened Images | unaffected 3.8.13-1.hum1 * rpm | Not specified |
| CNA | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525684 * rpm | Not specified |
| CNA | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525671 * rpm | Not specified |
| CNA | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525693 * rpm | Not specified |
| CNA | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525739 * rpm | Not specified |
| CNA | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1787241211 * rpm | Not specified |
| CNA | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1787135742 * rpm | Not specified |
| CNA | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1787241260 * rpm | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 6 | Not specified | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 10 | unaffected 0:3.8.10-4.el10_2 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | unaffected 0:3.8.9-9.el10_0.19 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 7 Extended Lifecycle Support | unaffected 0:3.3.29-9.el7_9.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8 | unaffected 0:3.6.16-8.el8_10.6 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | unaffected 0:3.6.14-10.el8_4.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | unaffected 0:4.13-3.el8_4.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | unaffected 0:3.6.14-10.el8_4.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | unaffected 0:4.13-3.el8_4.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | unaffected 0:3.6.16-5.el8_6.5 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | unaffected 0:4.13-3.el8_6.2 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | unaffected 0:3.6.16-5.el8_6.5 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | unaffected 0:4.13-3.el8_6.2 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | unaffected 0:3.6.16-7.el8_8.4 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | unaffected 0:4.13-4.el8_8.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.8 Update Services For SAP Solutions | unaffected 0:3.6.16-7.el8_8.4 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 8.8 Update Services For SAP Solutions | unaffected 0:4.13-4.el8_8.1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 9 | unaffected 0:3.8.10-4.el9_8 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 9.2 Update Services For SAP Solutions | unaffected 0:3.7.6-21.el9_2.7 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 9.4 Update Services For SAP Solutions | unaffected 0:3.8.3-4.el9_4.6 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | unaffected 0:3.8.3-6.el9_6.4 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4.12 | unaffected 412.86.202608241157-0 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4.14 | unaffected 414.92.202608172040-0 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4.15 | unaffected 415.92.202608180329-0 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4.16 | unaffected 416.94.202608150307-0 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4.17 | unaffected 417.94.202608250221-0 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4.18 | unaffected 418.94.202608142238-0 * rpm | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4.19 | unaffected 4.19.9.6.202608182320-0 * rpm | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951051 * rpm | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951012 * rpm | Not specified |
| ADP | Red Hat | Red Hat AI Inference Server 3.2 | unaffected 1782951244 * rpm | Not specified |
| ADP | Red Hat | Red Hat Discovery 2 | unaffected 1782159791 * rpm | Not specified |
| ADP | Red Hat | Red Hat Discovery 2 | unaffected 1782166952 * rpm | Not specified |
| ADP | Red Hat | Red Hat Hardened Images | unaffected 3.8.13-1.hum1 * rpm | Not specified |
| ADP | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525684 * rpm | Not specified |
| ADP | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525671 * rpm | Not specified |
| ADP | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525693 * rpm | Not specified |
| ADP | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1781525739 * rpm | Not specified |
| ADP | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1787241211 * rpm | Not specified |
| ADP | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1787135742 * rpm | Not specified |
| ADP | Red Hat | Red Hat Update Infrastructure 5 | unaffected 1787241260 * rpm | Not specified |
| ADP | Red Hat | Red Hat Enterprise Linux 6 | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| access.redhat.com/errata/RHSA-2026:30004 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:36004 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:57483 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:30849 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| bugzilla.redhat.com/show_bug.cgi | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | bugzilla.redhat.com | |
| access.redhat.com/errata/RHSA-2026:56853 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:20611 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:58981 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:13274 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33846.json | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | security.access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:20613 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:36006 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:26319 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:32962 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:20612 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:34372 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:29197 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:60019 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:41921 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/security/cve/CVE-2026-33846 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:33125 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:59831 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:57402 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:36005 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:26409 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:56911 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:30850 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:56786 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-03-24T05:38:09.899Z | Reported to Red Hat. |
| CNA | 2026-05-04T08:53:59.249Z | Made public. |
| ADP | 2026-03-24T05:38:09.899Z | Reported to Red Hat. |
| ADP | 2026-05-04T08:53:59.249Z | Made public. |
Solutions
ADP: RHSA-2026:34372: Red Hat Enterprise Linux Server (v. 7 ELS)
ADP: RHSA-2026:59831: Red Hat OpenShift Container Platform 4.12
ADP: RHSA-2026:56786: Red Hat OpenShift Container Platform 4.14
ADP: RHSA-2026:56911: Red Hat OpenShift Container Platform 4.15
ADP: RHSA-2026:56853: Red Hat OpenShift Container Platform 4.16
ADP: RHSA-2026:60019: Red Hat OpenShift Container Platform 4.17
ADP: RHSA-2026:57483: Red Hat OpenShift Container Platform 4.18
ADP: RHSA-2026:57402: Red Hat OpenShift Container Platform 4.19
ADP: RHSA-2026:26409: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux BaseOS EUS (v. 10.0)
ADP: RHSA-2026:20613: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10)
ADP: RHSA-2026:20611: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux BaseOS (v. 8)
ADP: RHSA-2026:33125: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4), Red Hat Enterprise Linux BaseOS AUS (v.8.4), Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4)
ADP: RHSA-2026:30849: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6), Red Hat Enterprise Linux BaseOS AUS (v.8.6), Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6)
ADP: RHSA-2026:30850: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8), Red Hat Enterprise Linux BaseOS E4S (v.8.8), Red Hat Enterprise Linux BaseOS TUS (v.8.8)
ADP: RHSA-2026:41921: Red Hat Enterprise Linux AppStream E4S (v.9.2), Red Hat Enterprise Linux BaseOS E4S (v.9.2)
ADP: RHSA-2026:32962: Red Hat Enterprise Linux AppStream E4S (v.9.4), Red Hat Enterprise Linux BaseOS E4S (v.9.4)
ADP: RHSA-2026:30004: Red Hat Enterprise Linux AppStream EUS (v.9.6), Red Hat Enterprise Linux BaseOS EUS (v.9.6)
ADP: RHSA-2026:20612: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9)
ADP: RHSA-2026:36004: Red Hat AI Inference Server 3.2
ADP: RHSA-2026:36005: Red Hat AI Inference Server 3.2
ADP: RHSA-2026:36006: Red Hat AI Inference Server 3.2
ADP: RHSA-2026:29197: Red Hat Discovery 2
ADP: RHSA-2026:13274: Red Hat Hardened Images
ADP: RHSA-2026:58981: Red Hat Update Infrastructure 5
ADP: RHSA-2026:26319: Red Hat Update Infrastructure 5
Workarounds
CNA: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
ADP: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
There are currently no legacy QID mappings associated with this CVE.