CVE-2026-90797 Apache Software Foundation CVE debrief

Who should care

Defenders and administrators of Apache CouchDB instances should assess exposure and verify inventory for versions below 3.5.3. This includes operators, platform administrators, vulnerability management teams, and security teams who need to prioritize upgrading to version 3.5.3 to prevent potential denial-of-service attacks. Immediate attention is required to prevent system crashes or instability.

Why it matters

This vulnerability allows remote clients to cause a denial of service in Apache CouchDB 3.5.2 and below. Defenders should assess exposure, verify inventory, and prioritize upgrading to version 3.5.3.

• Denial of service through memory exhaustion
• Potential for system crashes or instability
• Need for version verification and inventory checks
• Priority for upgrading to version 3.5.3

Technical summary

An unlimited gzip decompression routine in chttpd in Apache CouchDB 3.5.2 and below allows any remote client to cause a denial of service via memory exhaustion through a POST /_session request. This issue arises from the lack of limits on gzip decompression, leading to potential memory exhaustion and system instability. The vulnerability is addressed in version 3.5.3, which imposes necessary limits on decompression routines. Defenders should prioritize upgrading to this version to mitigate the risk of denial-of-service attacks.

Defensive priority

Upgrade to version 3.5.3 to fix this issue. Assess exposure and verify inventory for Apache CouchDB versions below 3.5.3.

Recommended defensive actions

• Upgrade Apache CouchDB to version 3.5.3
• Assess exposure and verify inventory for Apache CouchDB versions below 3.5.3
• Monitor for potential denial-of-service attacks
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and source item provide details on the vulnerability and affected versions. However, limited information is available on potential exploitation or victim impact. Defenders should verify the inventory of Apache CouchDB instances and assess exposure to this vulnerability. The official CVE Program record and NIST NVD detail page offer additional context. Supplemental sources provide release notes and vendor advisories.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.