CVE-2025-47913 — agent
HIGHCVE-2025-47913 is a high-severity (CVSS 7.5) Reachable Assertion vulnerability in golang.org/x/crypto/ssh/agent. A fix is available for golang.org/x/crypto/ssh/agent — see the affected versions and patch details below.
golang.org/x/crypto/ssh/agent has a potential denial of service
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-47913.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2025-47913 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,238 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
golang.org/x/crypto/ssh/agentReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
SSH clients receiving SSH_AGENT_SUCCESS when expecting a typed response will panic and cause early termination of the client process.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | golang.org/x/crypto/ssh/agent | all versions | 0.43.0go get golang.org/x/crypto/ssh/agent@v0.43.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for golang.org/x/crypto/ssh/agent, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update golang.org/x/crypto/ssh/agent to 0.43.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-47913 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-47913 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-47913. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This vulnerability was marked as Important because it allows any malicious or misbehaving SSH agent to force a crash in the client process using a single valid protocol byte. The panic occurs before the client has a chance to validate message structure or recover, which means an attacker controlling—or…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Ceph Storage 7.1 | ceph-2:18.2.1-381.el8cp | RHSA-2026:2769 |
| Red Hat Enterprise Linux 10 | buildah-2:1.41.8-1.el10_1 | RHSA-2026:0436 |
| Red Hat Enterprise Linux 10 | podman-7:5.6.0-11.el10_1 | RHSA-2026:0545 |
| Red Hat Enterprise Linux 10.0 Extended Update Support | buildah-2:1.39.8-1.el10_0 | RHSA-2026:14868 |
| Red Hat Enterprise Linux 10.0 Extended Update Support | podman-6:5.4.0-15.el10_0 | RHSA-2026:5167 |
| Red Hat Enterprise Linux 8 | container-tools:rhel8-8100020260114090145.afee755d | RHSA-2026:0753 |
| Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | container-tools:rhel8-8060020260422144418.ad008a3a | RHSA-2026:10703 |
| Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | container-tools:rhel8-8060020260515174849.ad008a3a | RHSA-2026:19634 |
Frequently Asked Questions
Is CVE-2025-47913 in your dependencies?
O3 Security finds CVE-2025-47913 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.