GnuTLS DTLS Handshake integer underflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.3$0-$5k0.00

Summaryinfo

A vulnerability was found in GnuTLS. It has been classified as problematic. Affected is an unknown function of the component DTLS Handshake Handler. This manipulation causes integer underflow. This vulnerability is tracked as CVE-2026-33845. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability has been found in GnuTLS (unknown version) and classified as problematic. Affected by this vulnerability is an unknown code block of the component DTLS Handshake Handler. The manipulation with an unknown input leads to a integer underflow vulnerability. The CWE definition for the vulnerability is CWE-191. The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. As an impact it is known to affect availability. The summary by CVE is:

A flaw in GnuTLS DTLS handshake parsing allows malformed fragments with zero length and non-zero offset, leading to an integer underflow during reassembly and resulting in an out-of-bounds read. This issue is remotely exploitable and may cause information disclosure or denial of service.

The advisory is shared at access.redhat.com. This vulnerability is known as CVE-2026-33845 since 03/24/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/08/2026).

The vulnerability scanner Nessus provides a plugin with the ID 312106 (CentOS 9 : gnutls-3.8.10-4.el9), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (312106) and CERT Bund (WID-SEC-2026-1312). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • IBM MQ
  • Microsoft Azure Linux
  • Open Source GnuTLS
  • Red Hat OpenShift

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 9.1
NVD Vector: 🔒

CNA Base Score: 7.5
CNA Vector (redhat): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Integer underflow
CWE: CWE-191 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 312106
Nessus Name: CentOS 9 : gnutls-3.8.10-4.el9

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

03/24/2026 CVE reserved
04/30/2026 +36 days Advisory disclosed
04/30/2026 +0 days VulDB entry created
07/08/2026 +69 days VulDB entry last update

Sourcesinfo

Advisory: access.redhat.com
Status: Confirmed

CVE: CVE-2026-33845 (🔒)
GCVE (CVE): GCVE-0-2026-33845
GCVE (VulDB): GCVE-100-360337
CERT Bund: WID-SEC-2026-1312 - GnuTLS: Mehrere Schwachstellen

Entryinfo

Created: 04/30/2026 20:11
Updated: 07/08/2026 04:47
Changes: 04/30/2026 20:11 (60), 05/01/2026 22:51 (7), 05/05/2026 10:19 (2), 05/27/2026 07:36 (11), 06/03/2026 17:01 (1), 06/20/2026 01:33 (1), 07/08/2026 04:47 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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