A vulnerability was found in libsoup's WebSocket frame parsing implementation. (CVE-2026-15711)
A vulnerability in libsoup's WebSocket frame parsing allows a remote unauthenticated attacker to cause a denial of service by sending an oversized control frame that violates RFC 6455 length rules. The parser does not properly handle this protocol violation, leading to an internal crash. This affects applications using libsoup WebSockets and has a CVSS score of 7.5 (high severity). Red Hat has issued a security advisory with a patch available for Red Hat Enterprise Linux 9 and related variants.
AI Analysis
Technical Summary
The libsoup library fails to enforce the length restrictions for WebSocket control frames as specified in RFC 6455 §5.5, which require control frames to have payloads of 125 bytes or less. An attacker can exploit this by sending a non-compliant oversized control frame, causing the parser to mishandle the protocol violation and trigger an internal processing crash. This results in a remote denial of service against applications using libsoup WebSockets. The vulnerability is tracked as CVE-2026-15711 with a CVSS 3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H). Red Hat has released an update for Red Hat Enterprise Linux 9 to address this issue.
Potential Impact
Remote unauthenticated attackers can cause a denial of service by crashing applications that use libsoup WebSockets through sending oversized WebSocket control frames that violate protocol length rules. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
A security update is available from Red Hat for Red Hat Enterprise Linux 9 and related variants that fixes this vulnerability. Users should apply the update as described in the Red Hat advisory RHSA-2026:68234. No additional mitigation is required as the patch addresses the issue directly.
A vulnerability was found in libsoup's WebSocket frame parsing implementation. (CVE-2026-15711)
Description
A vulnerability in libsoup's WebSocket frame parsing allows a remote unauthenticated attacker to cause a denial of service by sending an oversized control frame that violates RFC 6455 length rules. The parser does not properly handle this protocol violation, leading to an internal crash. This affects applications using libsoup WebSockets and has a CVSS score of 7.5 (high severity). Red Hat has issued a security advisory with a patch available for Red Hat Enterprise Linux 9 and related variants.
CVSS v3.1
Score 7.5high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The libsoup library fails to enforce the length restrictions for WebSocket control frames as specified in RFC 6455 §5.5, which require control frames to have payloads of 125 bytes or less. An attacker can exploit this by sending a non-compliant oversized control frame, causing the parser to mishandle the protocol violation and trigger an internal processing crash. This results in a remote denial of service against applications using libsoup WebSockets. The vulnerability is tracked as CVE-2026-15711 with a CVSS 3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H). Red Hat has released an update for Red Hat Enterprise Linux 9 to address this issue.
Potential Impact
Remote unauthenticated attackers can cause a denial of service by crashing applications that use libsoup WebSockets through sending oversized WebSocket control frames that violate protocol length rules. There is no impact on confidentiality or integrity, only availability is affected.
Mitigation Recommendations
A security update is available from Red Hat for Red Hat Enterprise Linux 9 and related variants that fixes this vulnerability. Users should apply the update as described in the Red Hat advisory RHSA-2026:68234. No additional mitigation is required as the patch addresses the issue directly.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-w948-qrw5-cffc
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-15711"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
- State
- PUBLISHED
Patch Information
Threat ID: 6aab49bc55bf5e2cf5992a4c
Added to database: 09/17/2026, 02:00:28 UTC
Last enriched: 09/17/2026, 02:01:54 UTC
Last updated: 09/17/2026, 02:01:54 UTC
Views: 1
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