CVE-2026-3904
Summary
| CVE | CVE-2026-3904 |
|---|---|
| State | PUBLISHED |
| Assigner | glibc |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-03-11 14:16:30 UTC |
| Updated | 2026-04-09 20:31:38 UTC |
| Description | Calling NSS-backed functions that support caching via nscd may call the nscd client side code and in the GNU C Library version 2.36 under high load on x86_64 systems, the client may call memcmp on inputs that are concurrently modified by other processes or threads and crash. The nscd client in the GNU C Library uses the memcmp function with inputs that may be concurrently modified by another thread, potentially resulting in spurious cache misses, which in itself is not a security issue. However in the GNU C Library version 2.36 an optimized implementation of memcmp was introduced for x86_64 which could crash when invoked with such undefined behaviour, turning this into a potential crash of the nscd client and the application that uses it. This implementation was backported to the 2.35 branch, making the nscd client in that branch vulnerable as well. Subsequently, the fix for this issue was backported to all vulnerable branches in the GNU C Library repository. It is advised that distributions that may have cherry-picked the memcpy SSE2 optimization in their copy of the GNU C Library, also apply the fix to avoid the potential crash in the nscd client. |
Risk And Classification
Primary CVSS: v3.1 6.2 MEDIUM from ADP
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.000140000 probability, percentile 0.023040000 (date 2026-04-15)
Problem Types: CWE-366 | CWE-366 CWE-366 Race condition within a thread
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 6.2 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 6.2 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD Known Affected Configurations (CPE 2.3)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | The GNU C Library | Glibc | affected 2.35 2.37 custom | x86 |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| sourceware.org/bugzilla/show_bug.cgi | 3ff69d7a-14f2-4f67-a097-88dee7810d18 | sourceware.org | Exploit, Issue Tracking, Patch |
| sourceware.org/git | 3ff69d7a-14f2-4f67-a097-88dee7810d18 | sourceware.org | Patch |
| sourceware.org/git | 3ff69d7a-14f2-4f67-a097-88dee7810d18 | sourceware.org | Patch |
| sourceware.org/git | 3ff69d7a-14f2-4f67-a097-88dee7810d18 | sourceware.org | Third Party Advisory |
| www.openwall.com/lists/oss-security/2026/03/11/5 | af854a3a-2127-422b-91ae-364da2661108 | www.openwall.com | Mailing List, Third Party Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.