CVE-2026-39833: Golang go.crypto · The in-memory keyring returned by NewKeyring() silently accepted keys with the
Affects golang-go.cryptoSource GCVE Database
Not known to be exploited · CVSS 9.1 Critical · fixed in 1:0.0~git20151201.0.7b85b09-2ubuntu0.1~esm2 : patch golang-go.crypto as a priority.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 40% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1:0.0~git20151201.0.7b85b09-2ubuntu0.1~esm2, 2.0.11-0ubuntu1~16.04.4+esm3, 3.0.3-0ubuntu1~18.04.2+esm3 +5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 22 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10snapdpkg:deb/ubuntu/snapd?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSsnapdpkg:deb/ubuntu/snapd?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu Pro 26.04 LTSgolang-go.cryptopkg:deb/ubuntu/golang-go.crypto?arch=source&distro=esm-apps/resoluteOther threats | Affected
| Fixed in
|
Ubuntu 25.10golang-go.cryptopkg:deb/ubuntu/golang-go.crypto?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 25.10snapdpkg:deb/ubuntu/snapd?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSsnapdpkg:deb/ubuntu/snapd?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
The in-memory keyring returned by NewKeyring() silently accepted keys with the ConfirmBeforeUse constraint but never enforced it. The key would sign without any confirmation prompt, with no indication to the caller that the constraint was not in effect. NewKeyring() now returns an error when unsupported constraints are requested.
References
- ubuntu.com/security/CVE-2026-39833 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-39833 (opens in a new tab)
- go.dev/issue/79436 (opens in a new tab)
- go.dev/cl/778640 (opens in a new tab)
- go.dev/cl/778641 (opens in a new tab)
- groups.google.com/g/golang-announce/c/a082jnz-LvI (opens in a new tab)
- pkg.go.dev/vuln/GO-2026-5005 (opens in a new tab)
- github.com/golang/crypto/commit/0fb843a472225645e917c84f1f9744757f0bab14 (opens in a new tab)
- ubuntu.com/security/notices/USN-8447-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8447-2 (opens in a new tab)