CVE-2026-90797

HIGH 7.7

Published 2026-10-20 · Last modified 2026-10-20

An unlimited gzip decompression routine in chttpd in Apache CouchDB 3.5.2 and below on all platforms allows any remote client to cause a denial of service via memory exhaustion. Users are recommended to upgrade to version 3.5.3, which fixes this issue.

ELEVATED IMPACT

Severe if exploited (CVSS 7.7), but no known exploitation and low modeled probability. Patch on a normal cadence.

Exploitation likelihood

—EPSS not yet scored

○ In CISA KEV ○ Public exploit / PoC

Impact if exploited

7.7CVSS 4.0 · HIGH

ConfidentialityNone
IntegrityNone
AvailabilityHigh

What an attacker needs

✓Access: Reachable over the network — no local access needed
✓Privileges: No account or privileges required
✓User interaction: No user interaction needed
✓Complexity: No special conditions — reliably repeatable
✓Requirements: No special attack requirements

✓ lowers the bar for an attacker · ⚠ raises it

Proof of concept & exploit code

github-search Search GitHub for public PoC repos

Test against your own equipment

curl -s https://vulnpedia.com/cve/CVE-2026-90797/poc.jsonMachine-readable PoC index for this CVE (for automation).

Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-90797/poc.json

Affected

Vendors Apache Software Foundation

Products Apache Couchdb

Weakness (CWE)

CWE-409: Improper Handling of Highly Compressed Data (Data Amplification)

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:U/S:N/AU:Y/R:A/V:D/RE:M/U:Red

All CVSS metrics

HIGH 7.7 v4.0 · CNA Primary
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:U/S:N/AU:Y/R:A/V:D/RE:M/U:Red
HIGH 7.7 v4.0 · NVD Secondary
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:N/AU:Y/R:A/V:D/RE:M/U:Red

References

Sources: NVD · CVE.org · EPSS