An update for python-kdcproxy is now available for openEuler-22.03-LTS-SP3,openEuler-22.03-LTS-SP4,openEuler-24.03-LTS,openEuler-24.03-LTS-SP1,openEuler-24.03-LTS-SP2,openEuler-20.03-LTS-SP4 Security Advisory openeuler-security@openeuler.org openEuler security committee openEuler-SA-2025-2720 Final 1.0 1.0 2025-11-22 Initial 2025-11-22 2025-11-22 openEuler SA Tool V1.0 2025-11-22 python-kdcproxy security update An update for python-kdcproxy is now available for openEuler-22.03-LTS-SP3,openEuler-22.03-LTS-SP4,openEuler-24.03-LTS,openEuler-24.03-LTS-SP1,openEuler-24.03-LTS-SP2,openEuler-20.03-LTS-SP4 This package contains a Python WSGI module for proxying KDC requests over HTTP by following the MS-KKDCP protocol. It aims to be simple to deploy, with minimal configuration. Security Fix(es): If kdcproxy receives a request for a realm which does not have server addresses defined in its configuration, by default, it will query SRV records in the DNS zone matching the requested realm name. This creates a server-side request forgery vulnerability, since an attacker could send a request for a realm matching a DNS zone where they created SRV records pointing to arbitrary ports and hostnames (which may resolve to loopback or internal IP addresses). This vulnerability can be exploited to probe internal network topology and firewall rules, perform port scanning, and exfiltrate data. Deployments where the "use_dns" setting is explicitly set to false are not affected.(CVE-2025-59088) If an attacker causes kdcproxy to connect to an attacker-controlled KDC server (e.g. through server-side request forgery), they can exploit the fact that kdcproxy does not enforce bounds on TCP response length to conduct a denial-of-service attack. While receiving the KDC's response, kdcproxy copies the entire buffered stream into a new buffer on each recv() call, even when the transfer is incomplete, causing excessive memory allocation and CPU usage. Additionally, kdcproxy accepts incoming response chunks as long as the received data length is not exactly equal to the length indicated in the response header, even when individual chunks or the total buffer exceed the maximum length of a Kerberos message. This allows an attacker to send unbounded data until the connection timeout is reached (approximately 12 seconds), exhausting server memory or CPU resources. Multiple concurrent requests can cause accept queue overflow, denying service to legitimate clients.(CVE-2025-59089) An update for python-kdcproxy is now available for openEuler-22.03-LTS-SP3,openEuler-22.03-LTS-SP4,openEuler-24.03-LTS,openEuler-24.03-LTS-SP1,openEuler-24.03-LTS-SP2,openEuler-20.03-LTS-SP4. openEuler Security has rated this update as having a security impact of high. A Common Vunlnerability Scoring System(CVSS)base score,which gives a detailed severity rating, is available for each vulnerability from the CVElink(s) in the References section. High python-kdcproxy https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2025-2720 https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2025-59088 https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2025-59089 https://nvd.nist.gov/vuln/detail/CVE-2025-59088 https://nvd.nist.gov/vuln/detail/CVE-2025-59089 openEuler-22.03-LTS-SP3 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-20.03-LTS-SP4 python-kdcproxy-1.0.0-2.oe2203sp3.src.rpm python-kdcproxy-1.0.0-2.oe2203sp4.src.rpm python-kdcproxy-1.0.0-2.oe2403.src.rpm python-kdcproxy-1.0.0-2.oe2403sp1.src.rpm python-kdcproxy-1.0.0-2.oe2403sp2.src.rpm python-kdcproxy-1.0.0-2.oe2003sp4.src.rpm python3-kdcproxy-1.0.0-2.oe2203sp3.noarch.rpm python3-kdcproxy-1.0.0-2.oe2203sp4.noarch.rpm python3-kdcproxy-1.0.0-2.oe2403.noarch.rpm python3-kdcproxy-1.0.0-2.oe2403sp1.noarch.rpm python3-kdcproxy-1.0.0-2.oe2403sp2.noarch.rpm python3-kdcproxy-1.0.0-2.oe2003sp4.noarch.rpm If kdcproxy receives a request for a realm which does not have server addresses defined in its configuration, by default, it will query SRV records in the DNS zone matching the requested realm name. This creates a server-side request forgery vulnerability, since an attacker could send a request for a realm matching a DNS zone where they created SRV records pointing to arbitrary ports and hostnames (which may resolve to loopback or internal IP addresses). This vulnerability can be exploited to probe internal network topology and firewall rules, perform port scanning, and exfiltrate data. Deployments where the "use_dns" setting is explicitly set to false are not affected. 2025-11-22 CVE-2025-59088 openEuler-22.03-LTS-SP3 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-20.03-LTS-SP4 High 8.6 AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N python-kdcproxy security update 2025-11-22 https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2025-2720 If an attacker causes kdcproxy to connect to an attacker-controlled KDC server (e.g. through server-side request forgery), they can exploit the fact that kdcproxy does not enforce bounds on TCP response length to conduct a denial-of-service attack. While receiving the KDC's response, kdcproxy copies the entire buffered stream into a new buffer on each recv() call, even when the transfer is incomplete, causing excessive memory allocation and CPU usage. Additionally, kdcproxy accepts incoming response chunks as long as the received data length is not exactly equal to the length indicated in the response header, even when individual chunks or the total buffer exceed the maximum length of a Kerberos message. This allows an attacker to send unbounded data until the connection timeout is reached (approximately 12 seconds), exhausting server memory or CPU resources. Multiple concurrent requests can cause accept queue overflow, denying service to legitimate clients. 2025-11-22 CVE-2025-59089 openEuler-22.03-LTS-SP3 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-20.03-LTS-SP4 Medium 5.9 AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H python-kdcproxy security update 2025-11-22 https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2025-2720