Caddy: Unbounded body buffer via {http.request.body} placeholder — memory exhaustion DoS
Priority HIGH 70CWE-770Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-770.
Summary
Caddy is an extensible server platform that uses TLS by default. In version 2.11.3 and earlier, in modules/caddyhttp/replacer.go, resolving http.request.body reads the complete request body with an unbounded io.Copy before request-body middleware limits apply, allowing memory exhaustion and process termination.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00388 33rd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| caddyserver | caddy | up to 2.11.3 | — | No fix listed | CNA |
- caddy Vendorcaddyserver Affected up to 2.11.3 Fixed in — No fix listed CNA
CPE names Threatist (inferred) · 1
Inferred from how NVD named this product before; not given by a source.
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:caddyserver:caddy:*:*:*:*:*:*:*:* | — | — | caddyserver |
- cpe:2.3:a:caddyserver:caddy:*:*:*:*:*:*:*:* Versions — — ·caddyserver
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-92284
More caddyserver vulnerabilities
- TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
- TI-2026-21978 Improper input validation in caddyserver caddy CVSS 4.0HIGH 8.9
- TI-2026-21974 Caddy's mTLS client authentication silently fails open when CA certificate file is missing or malformed CVSS 4.0HIGH 8.8
- TI-2026-23680 Improper authentication in caddyserver caddy CVSS 3.1HIGH 8.8
- TI-2026-21976 Caddy: MatchHost becomes case-sensitive for large host lists (>100), enabling host-based route/auth bypass CVSS 4.0HIGH 7.7
- TI-2026-21975 Caddy: MatchPath %xx (escaped-path) branch skips case normalization, enabling path-based route/auth bypass CVSS 4.0HIGH 7.7
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences