Findings

CVE-2026-3547

VU#948176: Multiple TLS Libraries can Bypass Delegation Enforcement

Published Mar 19, 2026 · updated Jun 17, 2026 · wolfssl wolfssl

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.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Jun 17, 2026 · NIST NVD

    Updated

    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 comp

  2. Oct 15, 2026 · CERT/CC Vulnerability Notes

    Detected

    Overview This note covers thirteen library-specific records (VU#948176.6, .8–.19) of how widely used TLS libraries apply X.509 Name Constraints. The records describe cases where a constrained name may be accepted by one library and rejected by another. Some are fixed, some remain under review, and some were not accepted as security issues. Description Name Constraints are meant to keep a subordina

Affected

  • cpe wolfssl/wolfsslversion unspecified

Sources

  • CERT/CC Vulnerability NotesGovernment advisoryCVE-2026-3547

    Overview This note covers thirteen library-specific records (VU#948176.6, .8–.19) of how widely used TLS libraries apply X.509 Name Constraints. The records describe cases where a constrained name may be accepted by one library and rejected by another. Some are fixed, some remain

    kb.cert.org
  • CVE.orgVulnerability recordCVE-2026-3547

    Official CVE identifier

    cve.org
  • NIST NVDVulnerability recordCVE-2026-3547

    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 pot

    nvd.nist.gov

References