CVE-2026-28898: 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. in Apple swift-nio-http2
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.
AI Analysis
Technical Summary
CVE-2026-28898 describes a vulnerability in Apple’s swift-nio-http2 library where the HTTP/2-to-HTTP/1.1 codec failed to validate pseudo-header values for control characters before placing them into the translated HTTP/1.1 message. Specifically, pseudo-header fields like :path, :authority, :scheme, :method, and :status could contain carriage return (CR), line feed (LF), or null (NUL) bytes, which were not previously checked. This lack of validation could lead to malformed HTTP/1.1 messages. The vulnerability is addressed in swift-nio-http2 version 1.44.1, which adds validation at both the HPACK header validation layer and the translation layer to reject requests or responses containing these control characters with a connection error.
Potential Impact
The vulnerability allows injection of control characters into HTTP/1.1 messages via pseudo-header values, which could potentially lead to improper message parsing or handling. The CVSS score of 5.3 (medium severity) indicates limited impact, with confidentiality affected but no impact on integrity or availability. There are no known exploits in the wild.
Mitigation Recommendations
This issue is fixed in swift-nio-http2 version 1.44.1. Users should upgrade to version 1.44.1 or later to ensure validation of pseudo-header values and rejection of invalid control characters. No additional mitigation is indicated by the vendor advisory.
CVE-2026-28898: 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. in Apple swift-nio-http2
Description
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.
CVSS v3.1
Score 5.3medium
Affected software
pkg:swift/apple/swift-nio-http2Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-28898 describes a vulnerability in Apple’s swift-nio-http2 library where the HTTP/2-to-HTTP/1.1 codec failed to validate pseudo-header values for control characters before placing them into the translated HTTP/1.1 message. Specifically, pseudo-header fields like :path, :authority, :scheme, :method, and :status could contain carriage return (CR), line feed (LF), or null (NUL) bytes, which were not previously checked. This lack of validation could lead to malformed HTTP/1.1 messages. The vulnerability is addressed in swift-nio-http2 version 1.44.1, which adds validation at both the HPACK header validation layer and the translation layer to reject requests or responses containing these control characters with a connection error.
Potential Impact
The vulnerability allows injection of control characters into HTTP/1.1 messages via pseudo-header values, which could potentially lead to improper message parsing or handling. The CVSS score of 5.3 (medium severity) indicates limited impact, with confidentiality affected but no impact on integrity or availability. There are no known exploits in the wild.
Mitigation Recommendations
This issue is fixed in swift-nio-http2 version 1.44.1. Users should upgrade to version 1.44.1 or later to ensure validation of pseudo-header values and rejection of invalid control characters. No additional mitigation is indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- apple
- Date Reserved
- 2026-03-03T16:36:03.983Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a3d7af74853345fc155f0e7
Added to database: 06/25/2026, 19:01:11 UTC
Last enriched: 07/16/2026, 11:00:10 UTC
Last updated: 08/09/2026, 00:41:13 UTC
Views: 63
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