CVE-2026-89090: Denial of service in the event stream header decoder in AWS SDK for Go v2
Telemetry drift only. No threshold crossed and no authority ruling changed.
CVE record, CISA KEV and EPSS as of 2026-10-18.
CVEs like this one computed, by meaning
What to do now held facts and links
- Upgrade to 2026-03-23 or later CVE record
- Record your decision, dated and frozen with today's evidence: patch by a date · mitigated by a compensating control · deferred · accepted the risk · not affected
- Check your version against the ranges this record publishes.
What it is stated by the CNA
An unrecovered panic in the event stream header decoder in Amazon AWS SDK for Go v2 before release-2026-03-23 might allow an unauthenticated remote actor to terminate the consuming application process via a crafted event stream response frame containing a header value type outside the valid range. To remediate this issue, users should upgrade to release-2026-03-23 or later, and patch any forked or derivative code.
- weakness
- CWE-248 Uncaught exception
- affected
- AWS SDK for Go v2
- versions
- No affected-version range in held sources.
- fixed in
- 2026-03-23
- fixed by package (from OSV advisories)
- github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream (Go): 1.7.8 GHSA-xmrv-pmrh-hhx2 GO-2026-5764github.com/aws/aws-sdk-go-v2/service/bedrockagentcore (Go): 1.15.2 GHSA-xmrv-pmrh-hhx2 GO-2026-5764github.com/aws/aws-sdk-go-v2/service/bedrockagentruntime (Go): 1.51.8 GHSA-xmrv-pmrh-hhx2 GO-2026-5764github.com/aws/aws-sdk-go-v2/service/bedrockruntime (Go): 1.50.4 GHSA-xmrv-pmrh-hhx2 GO-2026-5764github.com/aws/aws-sdk-go-v2/service/cloudwatchlogs (Go): 1.65.0 GHSA-xmrv-pmrh-hhx2 GO-2026-5764github.com/aws/aws-sdk-go-v2/service/iotsitewise (Go): 1.52.19 GHSA-xmrv-pmrh-hhx2 GO-2026-5764and 6 more packages in the OSV advisories
- severity
- 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- assigned by
- AMZN
- published
- 2026-09-11
check us github.com github.com aws.amazon.com
Exploit code held, dated
- exploit code
- None held in the PoC-in-GitHub feed. A public repository changes this brief.
What moved held, dated
| date | EPSS | event |
|---|---|---|
| 14 Sep 2026 | 0.00309 | |
| 28 Sep 2026 | 0.00305 |
2 observations held. A step marked with a scoring model moved because the measurement was replaced, not because the vulnerability changed.
Outside the record researched, cited
This section reads the record's references and adds cited findings from outside it. It needs an account. Everything above is held facts and is complete without it.
What would change this brief held, dated
- CISA KEV
- Not listed in the catalogue we hold. A listing changes this brief.
- exploit probability
- 0.00 on 2026-09-28 (FIRST's EPSS, a probability and not evidence of exploitation). Next band line: 10% (0.10). Crossing a line changes this brief.
- fix
- Held: 2026-03-23. A newer fix from the CNA or OSV changes this brief.
How to check this
Every value above is held with two dates: when it was true upstream (as_of) and when we recorded it (tx_from). Re-derive the exploit probability as it stood on any date:
SELECT value, source, source_version, as_of, tx_from
FROM volatile_valid_as_of('CVE-2026-89090', '2026-10-30T23:59:59.999999Z', now());