TI-2020-09959 Aliases CVE-2020-12457 GHSA-85m8-xxmw-3hpv

An issue was discovered in wolfSSL before 4.5.0.

LOW 36CWE-835Published 2020-08-21 · Updated 2024-08-04

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: No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-835.

Summary

An issue was discovered in wolfSSL before 4.5.0. It mishandles the change_cipher_spec (CCS) message processing logic for TLS 1.3. If an attacker sends ChangeCipherSpec messages in a crafted way involving more than one in a row, the server becomes stuck in the ProcessReply() loop, i.e., a denial of service.

Why it matters now

EPSS 0.01531 74th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:wolfssl:wolfssl::::::::	before 4.5.0	Vulnerable	wolfSSL

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:* Versions before 4.5.0 Vulnerable ·wolfSSL

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2020-12457
2026-10-03 Alias added: GHSA-85m8-xxmw-3hpv

References

Patch 1

https://github.com/wolfSSL/wolfssl/pull/2927

Advisory 1

https://github.com/wolfSSL/wolfssl/releases/tag/v4.5.0-stable

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