Linux Kernel up to 6.19.5 libceph process_auth_done buffer overflow

CVSS Meta Temp Score
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CTI Interest Score
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8.7$5k-$25k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.19.5 and classified as critical. The impacted element is the function process_auth_done of the component libceph. Such manipulation leads to buffer overflow. This vulnerability is uniquely identified as CVE-2026-43304. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.19.5. Affected by this issue is the function process_auth_done of the component libceph. The manipulation with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: libceph: define and enforce CEPH_MAX_KEY_LEN When decoding the key, verify that the key material would fit into a fixed-size buffer in process_auth_done() and generally has a sane length. The new CEPH_MAX_KEY_LEN check replaces the existing check for a key with no key material which is a) not universal since CEPH_CRYPTO_NONE has to be excluded and b) doesn't provide much value since a smaller than needed key is just as invalid as no key -- this has to be handled elsewhere anyway.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2026-43304 since 05/01/2026. The exploitation is known to be easy. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 07/08/2026).

The vulnerability scanner Nessus provides a plugin with the ID 325425 (Ubuntu 24.04 LTS : Linux kernel (NVIDIA) vulnerabilities (USN-8508-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.16 or 6.19.6 eliminates this vulnerability. Applying the patch 6405e8c680974bb74e2c98d5249fb52c7b12a6c6/8d745d38c88ecbed95f6b2b39857bf89f35a3244/e1dc45d97975f9db65694d234fbddf1915176e16/1b275bd49e58752efb83767a5d1aed41356c5e64/c1a0f5f1e5e7e98c36a362ec3d1fcfd9932931ed/d82467c07b03a27c3c5469b62bb3b726305a80bb/ac431d597a9bdfc2ba6b314813f29a6ef2b4a3bf is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (325425) and CERT Bund (WID-SEC-2026-1454). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Red Hat Enterprise Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • RESF Rocky Linux
  • Microsoft Azure Linux
  • Open Source Linux Kernel

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.9
VulDB Meta Temp Score: 8.7

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (Linux): 🔒

CVSSv2info

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

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / 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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Nessus ID: 325425
Nessus Name: Ubuntu 24.04 LTS : Linux kernel (NVIDIA) vulnerabilities (USN-8508-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.15.202/6.1.165/6.6.128/6.12.75/6.18.16/6.19.6
Patch: 6405e8c680974bb74e2c98d5249fb52c7b12a6c6/8d745d38c88ecbed95f6b2b39857bf89f35a3244/e1dc45d97975f9db65694d234fbddf1915176e16/1b275bd49e58752efb83767a5d1aed41356c5e64/c1a0f5f1e5e7e98c36a362ec3d1fcfd9932931ed/d82467c07b03a27c3c5469b62bb3b726305a80bb/ac431d597a9bdfc2ba6b314813f29a6ef2b4a3bf

Timelineinfo

05/01/2026 CVE reserved
05/08/2026 +7 days Advisory disclosed
05/08/2026 +0 days VulDB entry created
07/08/2026 +61 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-43304 (🔒)
GCVE (CVE): GCVE-0-2026-43304
GCVE (VulDB): GCVE-100-362072
CERT Bund: WID-SEC-2026-1454 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 05/08/2026 16:09
Updated: 07/08/2026 09:25
Changes: 05/08/2026 16:09 (59), 05/18/2026 01:31 (11), 06/15/2026 23:41 (7), 07/08/2026 09:25 (2)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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