CVE-2026-33846

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.
References
Link Resource
https://access.redhat.com/errata/RHSA-2026:13274
https://access.redhat.com/errata/RHSA-2026:20611
https://access.redhat.com/errata/RHSA-2026:20612
https://access.redhat.com/errata/RHSA-2026:20613
https://access.redhat.com/errata/RHSA-2026:26319
https://access.redhat.com/errata/RHSA-2026:26409
https://access.redhat.com/errata/RHSA-2026:29197
https://access.redhat.com/errata/RHSA-2026:30004
https://access.redhat.com/errata/RHSA-2026:30849
https://access.redhat.com/errata/RHSA-2026:30850
https://access.redhat.com/errata/RHSA-2026:32962
https://access.redhat.com/errata/RHSA-2026:33125
https://access.redhat.com/errata/RHSA-2026:34372
https://access.redhat.com/errata/RHSA-2026:36004
https://access.redhat.com/errata/RHSA-2026:36005
https://access.redhat.com/errata/RHSA-2026:36006
https://access.redhat.com/errata/RHSA-2026:41921
https://access.redhat.com/security/cve/CVE-2026-33846
https://bugzilla.redhat.com/show_bug.cgi?id=2450625
https://access.redhat.com/errata/RHSA-2026:13274
https://access.redhat.com/errata/RHSA-2026:20611
https://access.redhat.com/errata/RHSA-2026:20612
https://access.redhat.com/errata/RHSA-2026:20613
https://access.redhat.com/errata/RHSA-2026:26319
https://access.redhat.com/errata/RHSA-2026:26409
https://access.redhat.com/errata/RHSA-2026:29197
https://access.redhat.com/errata/RHSA-2026:30004
https://access.redhat.com/errata/RHSA-2026:30849
https://access.redhat.com/errata/RHSA-2026:30850
https://access.redhat.com/errata/RHSA-2026:32962
https://access.redhat.com/errata/RHSA-2026:33125
https://access.redhat.com/errata/RHSA-2026:34372
https://access.redhat.com/errata/RHSA-2026:36004
https://access.redhat.com/errata/RHSA-2026:36005
https://access.redhat.com/errata/RHSA-2026:36006
https://access.redhat.com/errata/RHSA-2026:41921
https://access.redhat.com/security/cve/CVE-2026-33846
https://bugzilla.redhat.com/show_bug.cgi?id=2450625
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33846.json
Configurations

No configuration.

History

20 Jul 2026, 12:18

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References () https://access.redhat.com/errata/RHSA-2026:41921 - () https://access.redhat.com/errata/RHSA-2026:41921 -

20 Jul 2026, 10:16

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References
  • () https://access.redhat.com/errata/RHSA-2026:41921 -

07 Jul 2026, 12:16

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References () https://access.redhat.com/errata/RHSA-2026:36004 - () https://access.redhat.com/errata/RHSA-2026:36004 -
References () https://access.redhat.com/errata/RHSA-2026:36005 - () https://access.redhat.com/errata/RHSA-2026:36005 -
References () https://access.redhat.com/errata/RHSA-2026:36006 - () https://access.redhat.com/errata/RHSA-2026:36006 -

06 Jul 2026, 20:16

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References
  • () https://access.redhat.com/errata/RHSA-2026:36005 -

06 Jul 2026, 18:16

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02 Jul 2026, 12:17

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01 Jul 2026, 20:17

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References
  • () https://access.redhat.com/errata/RHSA-2026:34372 -

30 Jun 2026, 03:18

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References
  • () https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33846.json -
References () https://access.redhat.com/errata/RHSA-2026:13274 - () https://access.redhat.com/errata/RHSA-2026:13274 -
References () https://access.redhat.com/errata/RHSA-2026:20611 - () https://access.redhat.com/errata/RHSA-2026:20611 -
References () https://access.redhat.com/errata/RHSA-2026:20612 - () https://access.redhat.com/errata/RHSA-2026:20612 -
References () https://access.redhat.com/errata/RHSA-2026:20613 - () https://access.redhat.com/errata/RHSA-2026:20613 -
References () https://access.redhat.com/errata/RHSA-2026:26319 - () https://access.redhat.com/errata/RHSA-2026:26319 -
References () https://access.redhat.com/errata/RHSA-2026:26409 - () https://access.redhat.com/errata/RHSA-2026:26409 -
References () https://access.redhat.com/errata/RHSA-2026:29197 - () https://access.redhat.com/errata/RHSA-2026:29197 -
References () https://access.redhat.com/errata/RHSA-2026:30004 - () https://access.redhat.com/errata/RHSA-2026:30004 -
References () https://access.redhat.com/errata/RHSA-2026:30849 - () https://access.redhat.com/errata/RHSA-2026:30849 -
References () https://access.redhat.com/errata/RHSA-2026:30850 - () https://access.redhat.com/errata/RHSA-2026:30850 -
References () https://access.redhat.com/errata/RHSA-2026:32962 - () https://access.redhat.com/errata/RHSA-2026:32962 -
References () https://access.redhat.com/errata/RHSA-2026:33125 - () https://access.redhat.com/errata/RHSA-2026:33125 -
References () https://access.redhat.com/security/cve/CVE-2026-33846 - () https://access.redhat.com/security/cve/CVE-2026-33846 -
References () https://bugzilla.redhat.com/show_bug.cgi?id=2450625 - () https://bugzilla.redhat.com/show_bug.cgi?id=2450625 -

29 Jun 2026, 22:16

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References
  • () https://access.redhat.com/errata/RHSA-2026:33125 -

29 Jun 2026, 12:16

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  • () https://access.redhat.com/errata/RHSA-2026:32962 -

29 Jun 2026, 09:16

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  • () https://access.redhat.com/errata/RHSA-2026:30849 -
  • () https://access.redhat.com/errata/RHSA-2026:30850 -

26 Jun 2026, 08:16

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References
  • () https://access.redhat.com/errata/RHSA-2026:30004 -

24 Jun 2026, 17:16

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References
  • () https://access.redhat.com/errata/RHSA-2026:29197 -

17 Jun 2026, 13:20

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References
  • () https://access.redhat.com/errata/RHSA-2026:26319 -
  • () https://access.redhat.com/errata/RHSA-2026:26409 -

02 Jun 2026, 16:16

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References
  • () https://access.redhat.com/errata/RHSA-2026:20612 -

01 Jun 2026, 21:16

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References
  • () https://access.redhat.com/errata/RHSA-2026:20613 -

27 May 2026, 04:16

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References
  • () https://access.redhat.com/errata/RHSA-2026:20611 -

04 May 2026, 14:16

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References
  • () https://access.redhat.com/errata/RHSA-2026:13274 -

04 May 2026, 10:15

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New CVE

Information

Published : 2026-05-04 10:15

Updated : 2026-07-20 12:18


NVD link : CVE-2026-33846

Mitre link : CVE-2026-33846

CVE.ORG link : CVE-2026-33846


JSON object : View

Products Affected

No product.

CWE
CWE-130

Improper Handling of Length Parameter Inconsistency