CVE intelligence and bounded remediation
CVE-2025-5987 — A flaw was found in libssh when using the ChaCha20 cipher with the OpenSSL library
A flaw was found in libssh when using the ChaCha20 cipher with the OpenSSL library. If an attacker manages to exhaust the heap space, this error is not detected and may lead to libssh using a partially initialized cipher context. This occurs because the OpenSSL error code returned aliases with the SSH_OK code, resulting in libssh not properly detecting the error returned by the OpenSSL library. This issue can lead to undefined behavior, including compromised data confidentiality and integrity or crashes.
- Severity
- High
- CVSS
- 8.1 (3.1)
- Published
- 2025-07-07
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-393
Affected products
- libssh / libssh
Matched remediation archetype
General vulnerability remediation
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Confirm the affected component, deployment paths, reachable interfaces, and enabled features from inventories and configuration, without probing production destructively.
- Compare the advisory's affected conditions with the repository lockfiles, build manifests, artifacts, and runtime inventory.
- Identify data sensitivity, trust boundaries, and privilege level for every confirmed affected deployment.
Remediate safely
- Apply a vendor-supported fix or remove the affected component or feature; record the selected change and its source in the repository.
- Update direct and transitive dependency locks, generated artifacts, deployment manifests, and asset inventories together.
- Add a regression test for the documented unsafe condition using inert inputs and preserve rollback instructions.
Authoritative sources
Complete CVE record and remediation plan
The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.