Heap-based Buffer Overflow

Overview Affected versions of this package are vulnerable to Heap-based Buffer Overflow due to an integer underflow in the ECH extension parsing logic when calculating a buffer length, leading to writing beyond the bounds of an allocated buffer. An attacker can cause memory corruption or...

Out-of-bounds Write

Overview Affected versions of this package are vulnerable to Out-of-bounds Write in the wcHpkeLabeledExtract function when processing an oversized ECH configuration. An attacker can cause a client crash or achieve remote code execution by sending a maliciously crafted ECH config from a TLS server...

EUVD-2026-13231

Stack Buffer Overflow in wcHpkeLabeledExtract via Oversized ECH Config. A vulnerability existed in wolfSSL 5.8.4 ECH Encrypted Client Hello support, where a maliciously crafted ECH config could cause a stack buffer overflow on the client side, leading to potential remote execution and client...

EUVD-2026-13168

Heap Overflow in TLS 1.3 ECH parsing. An integer underflow existed in ECH extension parsing logic when calculating a buffer length, which resulted in writing beyond the bounds of an allocated buffer. Note that in wolfSSL, ECH is off by default, and the ECH standard is still evolving...

CVE-2026-3849

Stack Buffer Overflow in wcHpkeLabeledExtract via Oversized ECH Config. A vulnerability existed in wolfSSL 5.8.4 ECH Encrypted Client Hello support, where a maliciously crafted ECH config could cause a stack buffer overflow on the client side, leading to potential remote execution and client...

DEBIAN-CVE-2026-3849

Stack Buffer Overflow in wcHpkeLabeledExtract via Oversized ECH Config. A vulnerability existed in wolfSSL 5.8.4 ECH Encrypted Client Hello support, where a maliciously crafted ECH config could cause a stack buffer overflow on the client side, leading to potential remote execution and client...

CVE-2026-3549

Heap Overflow in TLS 1.3 ECH parsing. An integer underflow existed in ECH extension parsing logic when calculating a buffer length, which resulted in writing beyond the bounds of an allocated buffer. Note that in wolfSSL, ECH is off by default, and the ECH standard is still evolving...

DEBIAN-CVE-2026-3549

Heap Overflow in TLS 1.3 ECH parsing. An integer underflow existed in ECH extension parsing logic when calculating a buffer length, which resulted in writing beyond the bounds of an allocated buffer. Note that in wolfSSL, ECH is off by default, and the ECH standard is still evolving...

CVE-2026-3849

Stack Buffer Overflow in wcHpkeLabeledExtract via Oversized ECH Config. A vulnerability existed in wolfSSL 5.8.4 ECH Encrypted Client Hello support, where a maliciously crafted ECH config could cause a stack buffer overflow on the client side, leading to potential remote execution and client...

CVE-2026-3549

Heap Overflow in TLS 1.3 ECH parsing. An integer underflow existed in ECH extension parsing logic when calculating a buffer length, which resulted in writing beyond the bounds of an allocated buffer. Note that in wolfSSL, ECH is off by default, and the ECH standard is still evolving...

UBUNTU-CVE-2026-3849

Stack Buffer Overflow in wcHpkeLabeledExtract via Oversized ECH Config. A vulnerability existed in wolfSSL 5.8.4 ECH Encrypted Client Hello support, where a maliciously crafted ECH config could cause a stack buffer overflow on the client side, leading to potential remote execution and client...

UBUNTU-CVE-2026-3549

Heap Overflow in TLS 1.3 ECH parsing. An integer underflow existed in ECH extension parsing logic when calculating a buffer length, which resulted in writing beyond the bounds of an allocated buffer. Note that in wolfSSL, ECH is off by default, and the ECH standard is still evolving...

CVE-2026-3849 Buffer Overflow in HPKE via Oversized ECH Config

Stack Buffer Overflow in wcHpkeLabeledExtract via Oversized ECH Config. A vulnerability existed in wolfSSL 5.8.4 ECH Encrypted Client Hello support, where a maliciously crafted ECH config could cause a stack buffer overflow on the client side, leading to potential remote execution and client...

CVE-2026-3849

CVE-2026-3849 describes a stack buffer overflow in wolfSSL 5.8.4’s ECH (Encrypted Client Hello) support, specifically in wc_HpkeLabeledExtract triggered by an oversized ECH config. The issue could allow remote execution or a client crash when a malicious TLS server sends a crafted ECH config. ECH...

CVE-2026-3849

Stack Buffer Overflow in wcHpkeLabeledExtract via Oversized ECH Config. A vulnerability existed in wolfSSL 5.8.4 ECH Encrypted Client Hello support, where a maliciously crafted ECH config could cause a stack buffer overflow on the client side, leading to potential remote execution and client...

CVE-2026-3849

Stack Buffer Overflow in wcHpkeLabeledExtract via Oversized ECH Config. A vulnerability existed in wolfSSL 5.8.4 ECH Encrypted Client Hello support, where a maliciously crafted ECH config could cause a stack buffer overflow on the client side, leading to potential remote execution and client...

CVE-2026-3849 Buffer Overflow in HPKE via Oversized ECH Config

Stack Buffer Overflow in wcHpkeLabeledExtract via Oversized ECH Config. A vulnerability existed in wolfSSL 5.8.4 ECH Encrypted Client Hello support, where a maliciously crafted ECH config could cause a stack buffer overflow on the client side, leading to potential remote execution and client...

CVE-2026-3549 ECH parsing heap buffer overflow

Heap Overflow in TLS 1.3 ECH parsing. An integer underflow existed in ECH extension parsing logic when calculating a buffer length, which resulted in writing beyond the bounds of an allocated buffer. Note that in wolfSSL, ECH is off by default, and the ECH standard is still evolving...

CVE-2026-3549 ECH parsing heap buffer overflow

Heap Overflow in TLS 1.3 ECH parsing. An integer underflow existed in ECH extension parsing logic when calculating a buffer length, which resulted in writing beyond the bounds of an allocated buffer. Note that in wolfSSL, ECH is off by default, and the ECH standard is still evolving...

CVE-2026-3549

CVE-2026-3549 describes a heap overflow in TLS 1.3 ECH parsing due to an integer underflow while calculating a buffer length in the ECH extension parsing logic. The issue can cause writes beyond allocated buffers. Public sources consistently reference wolfSSL and note that ECH is off by default; ...