How severe is CVE-2026-39835?

CVE-2026-39835 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2026-39835 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-39835?

CVE-2026-39835 affects Golang Crypto. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-39835?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-39835 have an EU (EUVD) identifier?

Yes. CVE-2026-39835 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31393.

When was CVE-2026-39835 published?

CVE-2026-39835 was published on 2026-05-22 and last updated on 2026-07-08.

CVE-2026-39835

CVE-2026-39835 is a medium-severity vulnerability in Golang Crypto with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-295.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-31393
Weakness: CWE-295
Affected product: Golang Crypto
Published: 2026-05-22
Last modified: 2026-07-08

Description

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.

Frequently asked questions

What is CVE-2026-39835?: SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil.
How severe is CVE-2026-39835?: CVE-2026-39835 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2026-39835 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-39835?: CVE-2026-39835 affects Golang Crypto. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-39835?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-39835 have an EU (EUVD) identifier?: Yes. CVE-2026-39835 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31393.
When was CVE-2026-39835 published?: CVE-2026-39835 was published on 2026-05-22 and last updated on 2026-07-08.

References

Affected products (1)

cpe:2.3:a:golang:crypto:*:*:*:*:*:go:*:*

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