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TI-2026-03057 Aliases CVE-2026-3547GHSA-f377-557w-vjgv

wolfSSL: out-of-bounds read (DoS) in ALPN parsing due to incomplete validation

Priority LOW 39CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-125 and the CVSS impact.

Summary

Out-of-bounds read in ALPN parsing due to incomplete validation. wolfSSL 5.8.4 and earlier contained an out-of-bounds read in ALPN handling when built with ALPN enabled (HAVE_ALPN / --enable-alpn). A crafted ALPN protocol list could trigger an out-of-bounds read, leading to a potential process crash (denial of service). Note that ALPN is disabled by default, but is enabled for these 3rd party compatibility features: enable-apachehttpd, enable-bind, enable-curl, enable-haproxy, enable-hitch, enable-lighty, enable-jni, enable-nginx, enable-quic.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00296 22nd percentileScored 2026-11-07
Fix Fixed wolfSSL (wolfSSL): 5.9.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
wolfSSLwolfSSLbefore 5.9.05.9.0Patch availableCNA
  • wolfSSL VendorwolfSSL Affected before 5.9.0 Fixed in 5.9.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*before 5.9.0VulnerablewolfSSL
  • cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:* Versions before 5.9.0 Vulnerable ·wolfSSL

Remediation

  • Fix · CNA wolfSSL (wolfSSL) Fixed in 5.9.0

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    wolfSSL 5.9.0

    7 records Highest priority Priority MEDIUM 1 MEDIUM, 6 LOW

    Other records, highest priority first

    • TI-2026-03058 Buffer overflow in CRL number parsing in wolfSSLPriority MEDIUM 40
    • TI-2026-00601 Stack buffer overflow in PKCS7 SignedData encoding with custom signed attributesPriority LOW 12
    • TI-2026-03086 Non-constant time multiplication subroutine __muldi3 on RISC-V RV32IPriority LOW 11
    Show all 7 records →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-3547
  2. 2026-10-03 Alias added: GHSA-f377-557w-vjgv

References

Patch 1

  • TI-2024-00830 SEGV and out of bounds memory read from malicious packet CVSS 3.1CRITICAL 9.1
  • TI-2022-18557 In wolfSSL before 5.5.1, malicious clients can cause a buffer overflow during a TLS 1.3… CVSS 3.1HIGH 7.5
  • TI-2025-10943 Potential DoS Vulnerability through Multiple KeyShareEntry with Same Group in TLS 1.3 ClientHello CVSS 4.0MEDIUM 6.3
  • TI-2017-09737 wolfSSL Bleichenbacher/ROBOT CVSS 3.0HIGH 7.5
  • TI-2019-08902 wolfSSL 4.0.0 has a Buffer Overflow in DoPreSharedKeys in tls13.c when a current identity… CVSS 3.1CRITICAL 9.8
  • TI-2017-02021 Improper certificate validation in wolfSSL CVSS 3.1CRITICAL 9.8
See all 150 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences