Red Hat Enterprise Linux 10: Stack-based Buffer Overflow
CVE-2026-15370 is a high-severity stack-based buffer overflow vulnerability in Red Hat Enterprise Linux 10 from Red Hat, with a CVSS 3.1 base score of 7.3 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, but only if a user takes part, for example by opening a link or file. There is no confirmed exploitation so far. EPSS estimates a 0.17% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Libssh to 0.11.5 or a later version.
- Read the advisory on access.redhat.com for workarounds and exact fixed builds.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | Not specified in the record | Not stated |
| Red Hat | Red Hat Hardened Images | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 8 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 9 | Not specified in the record | Not stated |
| Libssh | Libssh | 0.11.0 up to, but not including, 0.11.5; 0.12.0 | 0.11.5 |
| Red Hat | Hardened Images | Not specified in the record | Not stated |
| Red Hat | Enterprise Linux | 10.0; 10.2 | Not stated |
| Red Hat | Enterprise Linux For Els | 10.2 | Not stated |
| Red Hat | Enterprise Linux For EUS | 10.2 | Not stated |
| Red Hat | Enterprise Linux For IBM Z Systems | 10.0; 10.2 | Not stated |
| Red Hat | Enterprise Linux For IBM Z Systems Els | 10.2 | Not stated |
| Red Hat | Enterprise Linux For IBM Z Systems EUS | 10.2 | Not stated |
| Red Hat | Enterprise Linux For Power Little Endian | 10.0; 10.2 | Not stated |
| Red Hat | Enterprise Linux For Power Little Endian Els | 10.2 | Not stated |
| Red Hat | Enterprise Linux For Power Little Endian EUS | 10.2 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- 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:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 6.7 | Medium | CNA (redhat.com) |
| CVSS 3.1 | 7.3 | High | NVD |
Official description
A flaw was found in libssh. During SFTP server directory listing, the longname field is constructed with unsafe concatenation into a fixed-size stack buffer. When a client causes the server to list attacker-controlled filenames, sufficiently long names can overflow that stack buffer and may lead to crashes or possible code execution on the server.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Stack-based Buffer Overflow
The product writes past the end of a buffer that was allocated on the stack.
How developers prevent this class of flaw
- 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.
- Use an abstraction library to abstract away risky APIs. Not a complete solution.
- Implement and perform bounds checking on input.
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
Advisories
Other vulnerabilities in Red Hat Enterprise Linux 10
- 8.8 High severity
- 7.5 High severity
- 7.5 High severity
- 7.9 High severity
- 7.3 High severity
- 7.5 High severity
Recent Stack-based Buffer Overflow vulnerabilities
- 8.8 High severity
- 9.8 Critical severity
- 7.8 High severity
- 8.1 High severity
DD-WRT Stack-Based Buffer Overflow Exploited
- 7.5 High severity
- 7.5 High severity
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