golang.org/x/net/http2: Loop with Unreachable Exit Condition
CVE-2026-33814 is a high-severity loop with unreachable exit condition vulnerability in golang.org/x/net/http2 from Golang.org/x/net, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 0.53.0 as the first without the flaw, so updating golang.org/x/net/http2 to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.84% chance of exploitation within 30 days, higher than 58% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update golang.org/x/net/http2 to 0.53.0 or a later version.
- Update net/http to 1.25.10 or 1.26.3, whichever matches your release line, or a later version.
- Read the advisory on pkg.go.dev for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
Version data comes from the organisation that assigned the CVE; 35 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.5 | High | NVD |
| CVSS 3.1 | 7.5 | High | CISA (ADP) |
| CVSS 3.1 | 7.5 | High | CNA |
Official description
When processing HTTP/2 SETTINGS frames, transport will enter an infinite loop of writing CONTINUATION frames if it receives a SETTINGS_MAX_FRAME_SIZE with a value of 0.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Loop with Unreachable Exit Condition
The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.
More Loop with Unreachable Exit Condition vulnerabilities (CWE-835)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Patches and release notes
Other references
- go.dev/issue/78476Issue Tracking, Mailing List
- access.redhat.com/errata/RHSA-2026:22112
- access.redhat.com/errata/RHSA-2026:22120
- access.redhat.com/errata/RHSA-2026:22121
- access.redhat.com/errata/RHSA-2026:23262
- access.redhat.com/errata/RHSA-2026:23264
- access.redhat.com/errata/RHSA-2026:33120
- access.redhat.com/errata/RHSA-2026:33123
- access.redhat.com/errata/RHSA-2026:33142
- access.redhat.com/errata/RHSA-2026:33150
- access.redhat.com/errata/RHSA-2026:34342
- access.redhat.com/errata/RHSA-2026:37387
- access.redhat.com/errata/RHSA-2026:42644
- access.redhat.com/errata/RHSA-2026:43692
- access.redhat.com/errata/RHSA-2026:49702
Other vulnerabilities in golang.org/x/net/http2
- 7.5 High severity
- 7.5 High severity
- 9.1 Critical severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
Recent Loop with Unreachable Exit Condition vulnerabilities
- 7.5 High severity
- 9.4 Critical severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
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