CVE-2025-61729: high-severity vulnerability in Go standard library crypto/x509
Excessive resource consumption when printing error string for host certificate validation in crypto/x509
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.5%
Within HostnameError.Error(), when constructing an error string, there is no limit to the number of hosts that will be printed out. Furthermore, the error string is constructed by repeated string concatenation, leading to quadratic runtime. Therefore, a certificate provided by a malicious actor can result in excessive resource consumption.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
Go standard library · crypto/x509Related CVEs — Go standard library crypto/x509
In the same product, most dangerous first.
CVE-2024-24783MEDIUMVerify panics on certificates with an unknown public key algorithm in crypto/x509EPSS 0.7%CVE-2026-27137HIGHIncorrect enforcement of email constraints in crypto/x509EPSS 0.7%CVE-2026-32280HIGHUnexpected work during chain building in crypto/x509EPSS 0.6%CVE-2025-22865HIGHParsePKCS1PrivateKey panic with partial keys in crypto/x509EPSS 0.6%CVE-2026-27145MEDIUMInefficient candidate hostname parsing in crypto/x509EPSS 0.6%CVE-2024-45341MEDIUMUsage of IPv6 zone IDs can bypass URI name constraints in crypto/x509EPSS 0.6%