CVE-2026-3230 | Improper key_share validation in TLS 1.3 HelloRetryRequest

Missing required cryptographic step in the TLS 1.3 client HelloRetryRequest handshake logic in wolfSSL could lead to a compromise in the confidentiality of TLS-protected communications via a crafted HelloRetryRequest followed by a ServerHello message that omits the required key_share extension, resulting in derivation of predictable traffic secrets from (EC)DHE shared secret. This issue does not affect the client's authentication of the server during TLS handshakes.

Published: 2026-03-19 Last update: 2026-03-26 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-3230 is rated Low Risk (13.8/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.09%). Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-3230

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-20 — 0.09% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-3230

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
1.2 4.0 LOW
CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/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:Y/R:A/V:D/RE:X/U:Clear Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:H)
Exploitation depends on constrained or hard-to-reproduce conditions.
Attack requirements (AT:P)
Additional preconditions must be present for exploitation.
Privileges required (PR:H)
High privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:L)
Limited confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N)
No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:P)
Proof-of-concept: public PoC exists; no reported exploitation and no known simplification tools.
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:Y)
Yes: all four kill-chain steps (reconnaissance, weaponization, delivery, exploitation) can be automated.
Recovery (supplemental) (R:A)
Automatic: services recover on their own after an attack.
Value density (supplemental) (V:D)
Diffuse: a single exploit event controls relatively limited resources (e.g., one client).
Vulnerability response effort (supplemental) (RE:X)
Not evaluated.
Provider urgency (supplemental) (U:CLEAR)
Clear: provider rates this as informational urgency.
 — — [email protected]
2.7 3.1 LOW
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 1.2 1.4 [email protected]

Weakness enumeration for CVE-2026-3230

OS Trackers for CVE-2026-3230

vendor priority summary link
alpine — CVE-2026-3230: 1 source package rows (wolfssl); 15 state rows across 2 repos (3.23-community, edge-community); fixed 0, open 15. https://security.alpinelinux.org/vuln/CVE-2026-3230
debian not yet assigned CVE-2026-3230 not yet assigned priority: Debian including 1 source packages (wolfssl), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-3230
ubuntu medium CVE-2026-3230 medium priority: Ubuntu including 1 source packages (wolfssl), 7 status rows across 7 suites (bionic, focal, jammy, noble, questing, upstream, xenial): needs-triage 6, released 1. https://ubuntu.com/security/CVE-2026-3230

Affected software / configurations for CVE-2026-3230

Vendor Product Version Raw CPE
wolfssl wolfssl < 5.9.0 cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

References for CVE-2026-3230

URL Tags
https://github.com/wolfSSL/wolfssl/pull/9754 Patch Issue Tracking
cvelogic Threat Intelligence