CVE-2026-39835: golang.org/x/crypto/ssh · NULL Pointer Dereference
Affects golang.org/x/crypto/sshSource CVE Database V5
Not known to be exploited · CVSS 5.3 Medium : upgrade to 0.52.0 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 42% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.52.0
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LExploitation evidence
Disclosed: evidence found.
CVE published 22 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade golang.org/x/crypto/ssh to 0.52.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| golang.org/x/cryptogolang.org/x/crypto/ssh | Affected
| Fixed in
|
Gogolang.org/x/crypto/sshpkg:golang/golang.org/x/crypto/sshOther threats | Affected
| Fixed in– |
Gogolang.org/x/crypto/sshpkg:golang/golang.org/x/crypto/sshOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Currently, no mitigation is available that meets Red Hat's criteria for ease of use, applicability, and stability. Red Hat is working on fixes and will release updates in affected products such as Red Hat Edge Manager. Until then, avoid using CertChecker without explicitly setting IsUserAuthority or IsHostAuthority callbacks if possible.
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.
References
- go.dev/issue/79563 (opens in a new tab)
- groups.google.com/g/golang-announce/c/a082jnz-LvI (opens in a new tab)
- go.dev/cl/781660 (opens in a new tab)
- pkg.go.dev/vuln/GO-2026-5015 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-39835 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2480680 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-39835.json (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:41019 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:48151 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:36796 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:36199 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:37072 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:38504 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:37410 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:37123 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:43692 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26546 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:36319 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:26547 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:36625 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:36207 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:36651 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:40945 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:40118 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:36648 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:41036 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:37387 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:42146 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:43052 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:42796 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:41066 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:41031 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:40262 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:40972 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:40974 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:40969 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:36797 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:37271 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:37268 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:37272 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:37286 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:37296 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:46885 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:47949 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:47735 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:51033 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:51038 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:52857 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:52910 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:51036 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:54525 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:57194 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:59467 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:59593 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:60520 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:62260 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:65126 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:66521 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:66022 (opens in a new tab)