How severe is CVE-2026-34715?

CVE-2026-34715 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-34715 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34715?

CVE-2026-34715 affects Vshakitskiy Ewe. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-34715?

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

Does CVE-2026-34715 have an EU (EUVD) identifier?

Yes. CVE-2026-34715 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18468.

When was CVE-2026-34715 published?

CVE-2026-34715 was published on 2026-04-02 and last updated on 2026-06-17.

CVE-2026-34715

CVE-2026-34715 is a medium-severity vulnerability in Vshakitskiy Ewe with a CVSS 3.x base score of 5.3. 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-113.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (25th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-18468
Weakness: CWE-113
Affected product: Vshakitskiy Ewe
Published: 2026-04-02
Last modified: 2026-06-17

Description

ewe is a Gleam web server. Prior to version 3.0.6, the encode_headers function in src/ewe/internal/encoder.gleam directly interpolates response header keys and values into raw HTTP bytes without validating or stripping CRLF (\r\n) sequences. An application that passes user-controlled data into response headers (e.g., setting a Location redirect header from a request parameter) allows an attacker to inject arbitrary HTTP response content, leading to response splitting, cache poisoning, and possible cross-site scripting. Notably, ewe does validate CRLF in incoming request headers via validate_field_value() in the HTTP/1.1 parser — but provides no equivalent protection for outgoing response headers in the encoder. This issue has been patched in version 3.0.6.

Frequently asked questions

What is CVE-2026-34715?: ewe is a Gleam web server. Prior to version 3.0.6, the encode_headers function in src/ewe/internal/encoder.gleam directly interpolates response header keys and values into raw HTTP bytes without validating or stripping CRLF (\r\n) sequences. An application that passes user-controlled data into response headers (e.g., setting a Location redirect header from a request parameter) allows an attacker to inject arbitrary HTTP response content, leading to response splitting, cache poisoning, and possible cross-site scripting. Notably, ewe does validate CRLF in incoming request headers via validate_field_value() in the HTTP/1.1 parser — but provides no equivalent protection for outgoing response headers in the encoder. This issue has been patched in version 3.0.6.
How severe is CVE-2026-34715?: CVE-2026-34715 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-34715 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34715?: CVE-2026-34715 affects Vshakitskiy Ewe. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-34715?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-34715 have an EU (EUVD) identifier?: Yes. CVE-2026-34715 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18468.
When was CVE-2026-34715 published?: CVE-2026-34715 was published on 2026-04-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:vshakitskiy:ewe:*:*:*:*:*:*:*:*

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