# CVE-2026-46598: Go x/crypto denial of service in SSH agent Ed25519 parsing

Source: https://junglewise.ai/threats/cve-2026-46598-go-x-crypto-denial-of-service-in-ssh-agent-ed25519-parsing  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-22. Updated: 2026-06-25  
License: CC BY 4.0 with a link back

CVE-2026-46598 · Severity: medium · CVSS 5.3 · Published 2026-05-22

A vulnerability in the Go SSH agent library can cause applications using it to crash when processing specifically malformed data. This could allow a remote attacker to disrupt services or disconnect users by sending "pathological" inputs that trigger a program panic. The issue primarily impacts the availability of services that rely on this library for SSH key management.

Technologies: [golang.org/x/crypto (Go)](https://junglewise.ai/threats/technologies/golang-org-x-crypto), [golang.org/x/crypto/ssh/agent (Go)](https://junglewise.ai/threats/technologies/golang-org-x-crypto-ssh-agent). Vendors: [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2026-46598 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-46598 being exploited in the wild.

**How severe is CVE-2026-46598?** Medium severity, with a CVSS score of 5.3, published 22 May 2026.

**Which products and versions are affected?** golang.org/x/crypto (Go) SEMVER:introduced=0,fixed=0.52.0; golang.org/x/crypto/ssh/agent (Go) < 0.52.0.

**Is there a fix for CVE-2026-46598?** Yes. golang.org/x/crypto (Go): upgrade to 0.52.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-46598 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-46598?** Check whether you run golang.org/x/crypto (Go) or golang.org/x/crypto/ssh/agent (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- golang.org/x/crypto (Go): upgrade to 0.52.0 or later

  ```sh
  go get golang.org/x/crypto@v0.52.0
  ```


## Technical details

A vulnerability exists in the golang.org/x/crypto/ssh/agent package where improper validation of array indices (CWE-129) occurs during the parsing of Ed25519 keys. Specifically, the library may attempt to create an 'ed25519.PrivateKey' by casting malformed wire bytes from untrusted network input. When these malformed objects are subsequently used, they trigger a runtime panic, leading to a denial-of-service. The issue affects the ForwardToAgent and ServeAgent functions. A fix is available in version 0.52.0 of the package.

## Affected products

- Go Project golang.org/x/crypto/ssh/agent < 0.52.0

## Identifiers

- CVE-2026-46598
- GHSA-9m57-25v3-79x9
- GO-2026-5033

## Timeline

- 2026-05-22: disclosed: Initial disclosure by the Go Project
- 2026-05-22: advisory: NVD published CVE-2026-46598
- 2026-06-25: patched: GitHub Advisory Database entry published/updated with version 0.52.0 fix

## References

- [https://go.dev/cl/781360](https://go.dev/cl/781360)
- [https://go.dev/issue/79596](https://go.dev/issue/79596)
- [https://groups.google.com/g/golang-announce/c/a082jnz-LvI](https://groups.google.com/g/golang-announce/c/a082jnz-LvI)
- [https://pkg.go.dev/vuln/GO-2026-5033](https://pkg.go.dev/vuln/GO-2026-5033)

## Related threats

- [Go SSH deadlock vulnerability in channel handling](https://junglewise.ai/threats/cve-2026-56855-go-ssh-deadlock-vulnerability-in-channel-handling)
- [Go x/crypto/ssh deadlock denial of service on undecided channel](https://junglewise.ai/threats/cve-2026-78662-go-2026-6354-prevent-dos-on-deadlocked-undecided-channel-in)
- [Go SSH source-address permission validation bypass in authentication callbacks](https://junglewise.ai/threats/cve-2026-56854-go-ssh-source-address-permission-validation-bypass-in)
- [GO-2026-5932 - The golang.org/x/crypto/openpgp package is unmaintained, unsafe by design, and has known security issues](https://junglewise.ai/threats/go-2026-5932-the-golang-org-x-crypto-openpgp-package-is-unmaintained-7e8ca4de)
- [Go x/crypto/ssh denial of service in AES-GCM decoder](https://junglewise.ai/threats/cve-2026-46597-go-x-crypto-ssh-denial-of-service-in-aes-gcm-decoder)