Envoy crashes when using an address type that isn’t supported by the OS
Envoy is a high-performance edge/middle/service proxy. Envoy crashes in Proxy protocol when using an address type that isn’t supported by the OS. Envoy is susceptible to crashing on a host with IPv6 disabled and a listener config with proxy protocol enabled when it receives a request where the client presents its IPv6 address. It is valid for a client to present its IPv6 address to a target server even though the whole chain is connected via IPv4. This issue has been addressed in released 1.29.1, 1.28.1, 1.27.3, and 1.26.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for help- Published
- Feb 9, 2024
- Updated
- Jun 17, 2026
- EPSS
- 0.8% · 53th percentile
- CWE
- CWE-248
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Report tools
Action score
30
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.8%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 7.5
- CNA · GitHub_M
- 7.5
- agree
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| envoyproxy | envoy | cpe:2.3:a:envoyproxy:envoy |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- envoyproxy envoy1.26.0 and later · before 1.26.7
- envoyproxy envoy1.27.0 and later · before 1.27.3
- envoyproxy envoy1.28.0 and later · before 1.28.1
- envoyproxy envoy1.29.0 and later · before 1.29.1
Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
envoyproxy envoy
- >= 1.29.0, < 1.29.1, >= 1.28.0, < 1.28.1, >= 1.27.0, < 1.27.3, < 1.26.7affected
Same product
envoyproxy: all recordsOther highest-scoring records for the same primary product.
- CVE-2024-30255HTTP/2: CPU exhaustion due to CONTINUATION frame flood56Plan
- CVE-2024-27919HTTP/2: memory exhaustion due to CONTINUATION frame flood56Plan
- CVE-2021-29492Bypass of path matching rules using escaped slash characters53Plan
- CVE-2019-15226Upon receiving each incoming request header data, Envoy will iterate over existing request headers to verify that the total size of the head49Plan
- CVE-2019-9901Envoy 1.9.0 and before does not normalize HTTP URL paths.41Plan
- CVE-2019-18802An issue was discovered in Envoy 1.12.0.40Plan
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2024-34363116 days apartEnvoy can crash due to uncaught nlohmann JSON exception30Monitor
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-248 · Uncaught ExceptionCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
- github.com/envoyproxy/envoy/commit/bacd3107455b8d387889467725eb72aa0d5b5237
- github.com/envoyproxy/envoy/security/advisories/GHSA-5m7c-mrwr-pm26
Vendor advisories and official records. Exploit/PoC links are deliberately left out.