CVE
CVE-2026-5503
CVE-2026-5503 wolfssl
In TLSXEchChangeSNI, the ctx->extensions branch set extensions unconditionally even when TLSXFind returned NULL. This caused TLSXUseSNI to attach the attacker-controlled publicName to the shared WOLFSSLCTX when no inner SNI was configured. TLSXEchRestoreSNI then failed to clean it up because its removal was gated on serverNameX != NULL. The inner ClientHello was sized before the pollution but written after it, causing TLSXSNI_Write to memcpy 255 bytes past the allocation boundary.
Package Versions Affected
Package Version
patch Availability
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CVSS Version
Severity
Base Score
CVSS Version
Score Vector
C
H
U
6.9
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4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
C
H
U
-
C
H
U
-
Related Resources
No items found.
References
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-5503
Basic Information
Ecosystem
