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CVE PROGRAM SOURCE RECORD7.5 High

CVE-2026-33846

Gnutls: gnutls: denial of service via heap buffer overflow in dtls handshake fragment reassembly

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Status
Published
Published
Updated
Assigning organization
redhat

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Red Hat Red Hat Enterprise Linux 10

Default version status: affected

  • 0:3.8.10-4.el10_2 to < *unaffected

Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support

Default version status: affected

  • 0:3.8.9-9.el10_0.19 to < *unaffected

Red Hat Red Hat Enterprise Linux 7 Extended Lifecycle Support

Default version status: affected

  • 0:3.3.29-9.el7_9.1 to < *unaffected

Red Hat Red Hat Enterprise Linux 8

Default version status: affected

  • 0:3.6.16-8.el8_10.6 to < *unaffected

Red Hat Red Hat Enterprise Linux 8

Default version status: affected

  • 0:3.6.16-8.el8_10.6 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support

Default version status: affected

  • 0:3.6.14-10.el8_4.1 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support

Default version status: affected

  • 0:4.13-3.el8_4.1 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

Default version status: affected

  • 0:3.6.14-10.el8_4.1 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

Default version status: affected

  • 0:4.13-3.el8_4.1 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support

Default version status: affected

  • 0:3.6.16-5.el8_6.5 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support

Default version status: affected

  • 0:4.13-3.el8_6.2 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On

Default version status: affected

  • 0:3.6.16-5.el8_6.5 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On

Default version status: affected

  • 0:4.13-3.el8_6.2 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service

Default version status: affected

  • 0:3.6.16-7.el8_8.4 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service

Default version status: affected

  • 0:4.13-4.el8_8.1 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions

Default version status: affected

  • 0:3.6.16-7.el8_8.4 to < *unaffected

Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions

Default version status: affected

  • 0:4.13-4.el8_8.1 to < *unaffected

Red Hat Red Hat Enterprise Linux 9

Default version status: affected

  • 0:3.8.10-4.el9_8 to < *unaffected

Red Hat Red Hat Enterprise Linux 9

Default version status: affected

  • 0:3.8.10-4.el9_8 to < *unaffected

Red Hat Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Default version status: affected

  • 0:3.7.6-21.el9_2.7 to < *unaffected

Red Hat Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

Default version status: affected

  • 0:3.8.3-4.el9_4.6 to < *unaffected

Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support

Default version status: affected

  • 0:3.8.3-6.el9_6.4 to < *unaffected

Red Hat Red Hat OpenShift Container Platform 4.12

Default version status: affected

  • 412.86.202608241157-0 to < *unaffected

Red Hat Red Hat OpenShift Container Platform 4.13

Default version status: affected

  • 413.92.202609080414-0 to < *unaffected

Red Hat Red Hat OpenShift Container Platform 4.14

Default version status: affected

  • 414.92.202608172040-0 to < *unaffected

Red Hat Red Hat OpenShift Container Platform 4.15

Default version status: affected

  • 415.92.202608180329-0 to < *unaffected

Red Hat Red Hat OpenShift Container Platform 4.16

Default version status: affected

  • 416.94.202608150307-0 to < *unaffected

Red Hat Red Hat OpenShift Container Platform 4.17

Default version status: affected

  • 417.94.202608250221-0 to < *unaffected

Red Hat Red Hat OpenShift Container Platform 4.18

Default version status: affected

  • 418.94.202608142238-0 to < *unaffected

Red Hat Red Hat OpenShift Container Platform 4.19

Default version status: affected

  • 4.19.9.6.202608182320-0 to < *unaffected

Red Hat Cert Manager support for Red Hat OpenShift release 1.17

Default version status: affected

  • 1791371080 to < *unaffected

Red Hat Cert Manager support for Red Hat OpenShift release 1.17

Default version status: affected

  • 1791371069 to < *unaffected

Red Hat Cert Manager support for Red Hat OpenShift release 1.17

Default version status: affected

  • 1791788287 to < *unaffected

Red Hat Cert Manager support for Red Hat OpenShift release 1.17

Default version status: affected

  • 1791970484 to < *unaffected

Red Hat Cert Manager support for Red Hat OpenShift release 1.18

Default version status: affected

  • 1791459707 to < *unaffected

Red Hat Cert Manager support for Red Hat OpenShift release 1.18

Default version status: affected

  • 1791459711 to < *unaffected

Red Hat Cert Manager support for Red Hat OpenShift release 1.18

Default version status: affected

  • 1791459759 to < *unaffected

Red Hat Cert Manager support for Red Hat OpenShift release 1.18

Default version status: affected

  • 1789029076 to < *unaffected

Red Hat Cert Manager support for Red Hat OpenShift release 1.18

Default version status: affected

  • 1791966259 to < *unaffected

Red Hat Cert Manager support for Red Hat OpenShift release 1.20

Default version status: affected

  • 1790598593 to < *unaffected

Red Hat Red Hat AI Inference Server 3.2

Default version status: affected

  • 1782951051 to < *unaffected

Red Hat Red Hat AI Inference Server 3.2

Default version status: affected

  • 1782951012 to < *unaffected

Red Hat Red Hat AI Inference Server 3.2

Default version status: affected

  • 1782951244 to < *unaffected

Red Hat Red Hat Discovery 2

Default version status: affected

  • 1782159791 to < *unaffected

Red Hat Red Hat Discovery 2

Default version status: affected

  • 1782166952 to < *unaffected

Red Hat Red Hat Hardened Images

Default version status: affected

  • 3.8.13-1.hum1 to < *unaffected

Red Hat Red Hat OpenShift AI 3.4

Default version status: affected

  • 1790703542 to < *unaffected

Red Hat Red Hat Update Infrastructure 5

Default version status: affected

  • 1781525684 to < *unaffected

Red Hat Red Hat Update Infrastructure 5

Default version status: affected

  • 1781525671 to < *unaffected

Red Hat Red Hat Update Infrastructure 5

Default version status: affected

  • 1781525693 to < *unaffected

Red Hat Red Hat Update Infrastructure 5

Default version status: affected

  • 1781525739 to < *unaffected

Red Hat Red Hat Update Infrastructure 5

Default version status: affected

  • 1787241211 to < *unaffected

Red Hat Red Hat Update Infrastructure 5

Default version status: affected

  • 1787135742 to < *unaffected

Red Hat Red Hat Update Infrastructure 5

Default version status: affected

  • 1787241260 to < *unaffected

Red Hat Red Hat Enterprise Linux 6

Default version status: unaffected

Red Hat Red Hat OpenShift Container Platform 4

Default version status: unknown

References