Red Hat Directory Server 11.5 E4S for RHEL 8: Heap-based Buffer Overflow
CVE-2025-14905 is a high-severity heap-based buffer overflow vulnerability in Red Hat Directory Server 11.5 E4S for RHEL 8 from Red Hat, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 1.29% chance of exploitation within 30 days, higher than 71% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of Red Hat Directory Server 11.5 E4S for RHEL 8 you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
Version data comes from the organisation that assigned the CVE; 1 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- HighAdministrator-level access is required first.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (redhat.com).
Official description
A flaw was found in the 389-ds-base server. A heap buffer overflow vulnerability exists in the `schema_attr_enum_callback` function within the `schema.c` file. This occurs because the code incorrectly calculates the buffer size by summing alias string lengths without accounting for additional formatting characters. When a large number of aliases are processed, this oversight can lead to a heap overflow, potentially allowing a remote attacker to cause a Denial of Service (DoS) or achieve Remote Code Execution (RCE).
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Heap-based Buffer Overflow
The product writes past the end of a buffer that was allocated on the heap.
How developers prevent this class of flaw
- Pre-design: Use a language or compiler that performs automatic bounds checking.
- Use an abstraction library to abstract away risky APIs. Not a complete solution.
- Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
- access.redhat.com/errata/RHSA-2026:3189
- access.redhat.com/errata/RHSA-2026:3208
- access.redhat.com/errata/RHSA-2026:3379
- access.redhat.com/errata/RHSA-2026:3504
- access.redhat.com/errata/RHSA-2026:4207
- access.redhat.com/errata/RHSA-2026:4661
- access.redhat.com/errata/RHSA-2026:4720
- access.redhat.com/errata/RHSA-2026:5196
- access.redhat.com/errata/RHSA-2026:5511
- access.redhat.com/errata/RHSA-2026:5512
- access.redhat.com/errata/RHSA-2026:5513
- access.redhat.com/errata/RHSA-2026:5514
- access.redhat.com/errata/RHSA-2026:5568
- access.redhat.com/errata/RHSA-2026:5569
- access.redhat.com/errata/RHSA-2026:5576
Other vulnerabilities in Red Hat Directory Server 11.5 E4S for RHEL 8
- 8.4 High severity
- 9.8 Critical severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
Recent Heap-based Buffer Overflow vulnerabilities
- 7.5 High severity
- 9.8 Critical severity
- 8.8 High severity
- 8.8 High severity
- 7.5 High severity
- 7.5 High severity
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