CVE-2026-28898 json
SwiftNIO HTTP/2: HTTP/2-to-HTTP/1 Request Smuggling via unvalidated :path pseudo-header in HTTP2ToHTTP1Codec
published 2026-06-12 4 mo ago modified 2026-10-25 14 d ago also EUVD-2026-39533 , GHSA-4px2-pw77-vc85
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 24%
- public exploits
- 0
- none known
Summary
swift-nio-http2's HTTP/2-to-HTTP/1.1 codec did not validate pseudo-header values for control characters before placing them into the translated HTTP/1.1 message. swift-nio-http2 1.44.1 adds validation of all pseudo-header values (:path, :authority, :scheme, :method, and :status) at both the HPACK header validation layer and the HTTP/2-to-HTTP/1.1 translation layer. Requests or responses containing CR, LF, or NUL bytes in any pseudo-header value are now rejected with a connection error. This issue is fixed in swift-nio-http2 1.44.1.
Patch / fix
- swift github.com/apple/swift-nio-http2 1.44.0
- Apple swift-nio-http2 1.44.1
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 4 mo ago
Exploit prediction
0.31% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
| GitHub | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| swift | github.com/apple/swift-nio-http2 | <1.44.0 |
1.44.0 |
Affected products
- Apple swift-nio-http2
Classification
References
-
github.com
/apple/swift-nio-http2/commit/61d1b44f6e4e118792be1cff88ee2bc0267c6f9a
web
-
github.com
/advisories/GHSA-4px2-pw77-vc85
third-party-advisory
-
github.com
/apple/swift-nio-http2/security/advisories/GHSA-4px2-pw77-vc85
web
-
nvd.nist.gov
/vuln/detail/CVE-2026-28898
advisory
-
github.com
/apple/swift-nio-http2
package
Sources
- CVE List CVE-2026-28898
- GitHub Advisory GHSA-4px2-pw77-vc85
- NVD CVE-2026-28898
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