CVE-2025-61729
crypto/x509: golang: Denial of Service due to excessive resource consumption via crafted certificate
Published Oct 16, 2026 · Red Hat · evidence confidence high
A flaw was found in golang. A remote attacker could exploit this vulnerability by providing a specially crafted certificate during the error string construction process within the function. This flaw, caused by unbounded string concatenation, leads to excessive resource consumption. Successful exploitation can result in a denial of service (DoS) for the affected system.
Grounded briefings
Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.
Executive
CVE-2025-61729 is a high public vulnerability record for Red Hat. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.
System administrator
Identify whether Red Hat is in your estate, then compare installed versions with the affected ranges. Affected version ranges have not been ingested yet. Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.
Security analyst
Signals on file: CVSS 7.5. It is not currently listed in the CISA Known Exploited catalog. Sources contributing to this record: csaf. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.
Exploitation and remediation
Exploitation evidence
Not listed as known exploited in CISA KEV. Not in CISA KEV or VulnCheck KEV.
Patch and remediation
No required-action text is stored yet. Use the vendor or CERT links in Sources for patch availability.
Safe detection guidance
Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Related Odoo Git fixes
Quoted Community commit messages that cite this CVE. Presence of a commit is not proof that every edition or backport includes the fix. Enterprise proprietary diffs are never shown here. Timeline
Dec 2, 2025 · referenced
update to go1.25.5
update to go1.25.5 These releases include 2 security fixes following the security policy: - crypto/x509: excessive resource consumption in printing error string for host certificate validation 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. HostnameError.Error() now limits the number of hosts and utilizes strings.Builder when constructing an error string. Thanks to Philippe Antoine (Catena cyber) for reporting this issue. This is CVE-2025-61729 and Go issue https://go.dev/issue/76445. - crypto/x509: excluded subdomain constraint does not restrict wildcard SANs An…
https://github.com/moby/moby/commit/6f9d1ec3fb8ca4dbbedb1ed91020d9190dd0d848
Timeline
Detection, updates, and resolution for this record.
Oct 16, 2026 · CSAF Advisories
Detected
A flaw was found in golang. A remote attacker could exploit this vulnerability by providing a specially crafted certificate during the error string construction process within the function. This flaw, caused by unbounded string concatenation, leads to excessive resource consumption. Successful exploitation can result in a denial of service (DoS) for the affected system.
Sources
- CSAF AdvisoriesVendor advisoryRHSA-2026:9848:CVE-2025-61729
A flaw was found in golang. A remote attacker could exploit this vulnerability by providing a specially crafted certificate during the error string construction process within the function. This flaw, caused by unbounded string concatenation, leads to excessive resource consumpti
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