How severe is CVE-2023-29406?

CVE-2023-29406 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2023-29406 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-29406?

CVE-2023-29406 affects Golang Go. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-29406?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-29406 published?

CVE-2023-29406 was published on 2023-07-11 and last updated on 2026-06-17.

CVE-2023-29406

CVE-2023-29406 is a medium-severity vulnerability in Golang Go with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-436.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-436
Affected product: Golang Go
Published: 2023-07-11
Last modified: 2026-06-17

Description

The HTTP/1 client does not fully validate the contents of the Host header. A maliciously crafted Host header can inject additional headers or entire requests. With fix, the HTTP/1 client now refuses to send requests containing an invalid Request.Host or Request.URL.Host value.

Frequently asked questions

What is CVE-2023-29406?: The HTTP/1 client does not fully validate the contents of the Host header. A maliciously crafted Host header can inject additional headers or entire requests. With fix, the HTTP/1 client now refuses to send requests containing an invalid Request.Host or Request.URL.Host value.
How severe is CVE-2023-29406?: CVE-2023-29406 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2023-29406 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-29406?: CVE-2023-29406 affects Golang Go. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-29406?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-29406 published?: CVE-2023-29406 was published on 2023-07-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*

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