MIT Kerberos 5 1.20.0/1.21.1 kdc/do_tgs_req.c improper authorization

CVSS Meta Temp Score
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CTI Interest Score
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7.6$0-$5k0.00

Summaryinfo

A vulnerability was found in MIT Kerberos 5 1.20.0/1.21.1. It has been declared as critical. The affected element is an unknown function of the file kdc/do_tgs_req.c. Such manipulation leads to improper authorization. This vulnerability is referenced as CVE-2023-39975. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in MIT Kerberos 5 1.20.0/1.21.1 (Network Authentication Software). It has been rated as critical. Affected by this issue is some unknown processing of the file kdc/do_tgs_req.c. The manipulation with an unknown input leads to a improper authorization vulnerability. Using CWE to declare the problem leads to CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. Impacted is confidentiality, integrity, and availability. CVE summarizes:

kdc/do_tgs_req.c in MIT Kerberos 5 (aka krb5) 1.21 before 1.21.2 has a double free that is reachable if an authenticated user can trigger an authorization-data handling failure. Incorrect data is copied from one ticket to another.

The weakness was published 08/16/2023 as 88a1701b423c13991a8064feeb26952d3641d840. The advisory is shared for download at github.com. This vulnerability is handled as CVE-2023-39975 since 08/07/2023. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1548.002.

Upgrading to version 1.21.2 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 88a1701b423c13991a8064feeb26952d3641d840 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.7
VulDB Meta Temp Score: 7.6

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

ADP CISA Base Score: 8.8
ADP CISA Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Improper authorization
CWE: CWE-285 / CWE-266
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kerberos 5 1.21.2
Patch: 88a1701b423c13991a8064feeb26952d3641d840

Timelineinfo

08/07/2023 🔍
08/16/2023 +9 days 🔍
08/16/2023 +0 days 🔍
02/26/2026 +925 days 🔍

Sourcesinfo

Vendor: mit.edu

Advisory: 88a1701b423c13991a8064feeb26952d3641d840
Status: Confirmed

CVE: CVE-2023-39975 (🔍)
GCVE (CVE): GCVE-0-2023-39975
GCVE (VulDB): GCVE-100-237320

Entryinfo

Created: 08/16/2023 17:51
Updated: 02/26/2026 08:40
Changes: 08/16/2023 17:51 (45), 09/10/2023 12:49 (11), 02/26/2026 08:40 (27)
Complete: 🔍
Cache ID: 216::103

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