High severity · published Dec 2, 2025
CVE-2025-61729
Excessive resource consumption when printing error string for host certificate validation in crypto/x509
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CR
crypto/x509 · Go standard library
before 1.24.11; 1.25.0 before 1.25.5 · source: vendor
GO
GO · Golang
before 1.24.11; 1.25.0 before 1.25.5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-61729
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-61729
Patch
https://go.dev/cl/725920
Issue Tracking
https://go.dev/issue/76445
Mailing List
https://groups.google.com/g/golang-announce/c/8FJoBkPddm4
Vendor Advisory
https://pkg.go.dev/vuln/GO-2025-4155
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