LibreSSL up to 3.6.2/3.7.2 src/lib/libssl/s3_lib.c ssl3_free use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.5$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in LibreSSL up to 3.6.2/3.7.2. This affects the function ssl3_free of the file src/lib/libssl/s3_lib.c. The manipulation results in use after free. This vulnerability is identified as CVE-2023-35784. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in LibreSSL up to 3.6.2/3.7.2. It has been classified as problematic. Affected is the function ssl3_free of the file src/lib/libssl/s3_lib.c. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

A double free or use after free could occur after SSL_clear in OpenBSD 7.2 before errata 026 and 7.3 before errata 004, and in LibreSSL before 3.6.3 and 3.7.x before 3.7.3. NOTE: OpenSSL is not affected.

The weakness was released 06/17/2023 as 1d6680b3682f8caba78c627dee60c76da6e20dd7. The advisory is shared for download at github.com. This vulnerability is traded as CVE-2023-35784 since 06/16/2023. There are known technical details, but no exploit is available.

Upgrading to version 3.6.3 or 3.7.3 eliminates this vulnerability. Applying the patch 1d6680b3682f8caba78c627dee60c76da6e20dd7 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.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-39781). Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

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

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

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
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: LibreSSL 3.6.3/3.7.3
Patch: 1d6680b3682f8caba78c627dee60c76da6e20dd7

Timelineinfo

06/16/2023 🔍
06/17/2023 +1 days 🔍
06/17/2023 +0 days 🔍
01/10/2026 +938 days 🔍

Sourcesinfo

Advisory: 1d6680b3682f8caba78c627dee60c76da6e20dd7
Status: Confirmed

CVE: CVE-2023-35784 (🔍)

GCVE (CVE): GCVE-0-2023-35784
GCVE (VulDB): GCVE-100-231756
EUVD: 🔍

Entryinfo

Created: 06/17/2023 07:51
Updated: 01/10/2026 16:56
Changes: 06/17/2023 07:51 (42), 07/14/2023 13:51 (11), 01/10/2026 16:56 (16)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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