GNU C Library __vsyslog_internal heap-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.8$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in GNU C Library. This affects the function __vsyslog_internal. Executing a manipulation can lead to heap-based overflow. This vulnerability is handled as CVE-2023-6246. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability has been found in GNU C Library (Software Library) (affected version not known) and classified as critical. This vulnerability affects the function __vsyslog_internal. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was released 01/31/2024. The advisory is shared for download at bugzilla.redhat.com. This vulnerability was named CVE-2023-6246 since 11/21/2023. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 09/01/2025).

The vulnerability scanner Nessus provides a plugin with the ID 239976 (TencentOS Server 4: glibc (TSSA-2024:0581)), 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 (239976) and CERT Bund (WID-SEC-2024-0246). Once again VulDB remains the best source for vulnerability data.

Affected

  • Ubuntu Linux
  • Gentoo Linux
  • Siemens SIMATIC S7
  • Open Source GNU libc
  • Dell Avamar
  • Dell integrated Dell Remote Access Controller

Productinfo

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Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.8

VulDB Base Score: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CNA Base Score: 8.4
CNA Vector (Red Hat, Inc.): 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 239976
Nessus Name: TencentOS Server 4: glibc (TSSA-2024:0581)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

11/21/2023 🔍
01/31/2024 +71 days 🔍
01/31/2024 +0 days 🔍
09/01/2025 +579 days 🔍

Sourcesinfo

Vendor: gnu.org

Advisory: 176931
Status: Not defined

CVE: CVE-2023-6246 (🔍)
GCVE (CVE): GCVE-0-2023-6246
GCVE (VulDB): GCVE-100-252436
CERT Bund: WID-SEC-2024-0246 - GNU libc: Mehrere Schwachstellen

Entryinfo

Created: 01/31/2024 01:47
Updated: 09/01/2025 17:40
Changes: 01/31/2024 01:47 (37), 02/22/2024 10:00 (2), 02/22/2024 10:04 (21), 06/17/2025 20:34 (17), 09/01/2025 17:40 (7)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

Discussion

 Anonymous User (+0)
3 years ago
Good morning,
Why is the attack vector Network since the vulnerability cannot be activated remotely and it is an LPE? The program that calls the syslog() function must have a very long name (argv [0]) or identifier (ident). A remote attacker has no control over these parameters.
Thanks for the support.
Best Regards.
TEAM CERT
 VulDB Community Team3 years ago
Qualys' statement is unclear whether it affects local scenarios only. We assume that network software using glibc might be affected as well.

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