Skip to main content

S2N Tls

2 CVEs product

Monthly

CVE-2026-16317 Jul 21, 20:12 HIGH PATCH This Week

Silent record suppression in AWS s2n-tls affects all TLS 1.3 connections (both client and server roles) because the AEAD implementation hardcodes the outer content_type (0x17) in the additional authenticated data instead of authenticating the actual wire byte, leaving that field outside the integrity tag. An active on-path attacker can selectively drop individual application_data records without either endpoint detecting tampering, causing HTTP request/response desynchronization or undetectable data loss on write-heavy workloads. Reported internally by Amazon (AMZN); no public exploit identified at time of analysis, and it is not listed in CISA KEV.

Information Disclosure AWS Suse S2N Tls
NVD GitHub
CVSS 4.0
8.3
EPSS
0.2%
CVE-2026-16318 Jul 21, 20:14 MEDIUM PATCH This Month

Memory leak in Amazon s2n-tls's QUIC transport parameters handler exposes server-side QUIC deployments to gradual heap exhaustion by unauthenticated remote clients. The flaw is rooted in incorrect allocator use during TLS 1.3 HelloRetryRequest (HRR) flows - a standard protocol exchange that can be deliberately forced by clients advertising key share groups the server will reject - causing up to approximately 64 KB of unreachable memory per handshake. No active exploitation or public exploit code has been identified; vendor-confirmed patch v1.7.6 is available.

Information Disclosure Suse Amazon S2N Tls
NVD GitHub
CVSS 4.0
6.9
EPSS
0.4%
EPSS 0% CVSS 8.3
HIGH PATCH This Week

Silent record suppression in AWS s2n-tls affects all TLS 1.3 connections (both client and server roles) because the AEAD implementation hardcodes the outer content_type (0x17) in the additional authenticated data instead of authenticating the actual wire byte, leaving that field outside the integrity tag. An active on-path attacker can selectively drop individual application_data records without either endpoint detecting tampering, causing HTTP request/response desynchronization or undetectable data loss on write-heavy workloads. Reported internally by Amazon (AMZN); no public exploit identified at time of analysis, and it is not listed in CISA KEV.

Information Disclosure AWS Suse +1
NVD GitHub
EPSS 0% CVSS 6.9
MEDIUM PATCH This Month

Memory leak in Amazon s2n-tls's QUIC transport parameters handler exposes server-side QUIC deployments to gradual heap exhaustion by unauthenticated remote clients. The flaw is rooted in incorrect allocator use during TLS 1.3 HelloRetryRequest (HRR) flows - a standard protocol exchange that can be deliberately forced by clients advertising key share groups the server will reject - causing up to approximately 64 KB of unreachable memory per handshake. No active exploitation or public exploit code has been identified; vendor-confirmed patch v1.7.6 is available.

Information Disclosure Suse Amazon +1
NVD GitHub

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy