Security Advisory – 23 Apr 2026

Security fixes and advisories that landed overnight. The update includes Ubuntu kernel notices and a NIST entry for OAuth2 Proxy. It is a daily security advisory summary with the main items listed first and the rest grouped by source. Updated 23 Apr 2026 16:05 GMT.

Top items

Ubuntu

USN-8204-1: Linux kernel (Raspberry Pi Real-time) vulnerabilities

Ubuntu says several security issues were found in the Linux kernel, with a separate EntrySign issue covering AMD Zen processors. The notice says a privileged attacker could use the flaw to load malicious CPU microcode and affect integrity and confidentiality.

• Published: 23 Apr 2026 10:00 GMT
• CVEs: CVE-2024-36347, CVE-2024-57795, CVE-2025-22022, CVE-2025-22111, CVE-2025-38022, CVE-2025-38234, CVE-2025-40164, CVE-2025-40325, CVE-2025-68206, CVE-2025-68254, CVE-2025-68255, CVE-2025-68256, CVE-2025-68257, CVE-2025-68258, CVE-2025-68259, CVE-2025-68261, CVE-2025-68263, CVE-2025-68264, CVE-2025-68265, CVE-2025-68266, CVE-2025-68291, CVE-2025-68325, CVE-2025-68332, CVE-2025-68335, CVE-2025-68336, CVE-2025-68337, CVE-2025-68344, CVE-2025-68345, CVE-2025-68346, CVE-2025-68347, CVE-2025-68349, CVE-2025-68354, CVE-2025-68362, CVE-2025-68363, CVE-2025-68364, CVE-2025-68366, CVE-2025-68367, CVE-2025-68369, CVE-2025-68371, CVE-2025-68372, CVE-2025-68374, CVE-2025-68378, CVE-2025-68379, CVE-2025-68380, CVE-2025-68724, CVE-2025-68727, CVE-2025-68728, CVE-2025-68732, CVE-2025-68733, CVE-2025-68740, CVE-2025-68741, CVE-2025-68742, CVE-2025-68744, CVE-2025-68746, CVE-2025-68753, CVE-2025-68755, CVE-2025-68756, CVE-2025-68757, CVE-2025-68758, CVE-2025-68759, CVE-2025-68763, CVE-2025-68764, CVE-2025-68765, CVE-2025-68766, CVE-2025-68767, CVE-2025-68769, CVE-2025-68770, CVE-2025-68771, CVE-2025-68772, CVE-2025-68773, CVE-2025-68774, CVE-2025-68775, CVE-2025-68776, CVE-2025-68777, CVE-2025-68778, CVE-2025-68780, CVE-2025-68782, CVE-2025-68783, CVE-2025-68785, CVE-2025-68786, CVE-2025-68787, CVE-2025-68788, CVE-2025-68794, CVE-2025-68795, CVE-2025-68796, CVE-2025-68797, CVE-2025-68798, CVE-2025-68799, CVE-2025-68800, CVE-2025-68801, CVE-2025-68804, CVE-2025-68806, CVE-2025-68808, CVE-2025-68809, CVE-2025-68810, CVE-2025-68811, CVE-2025-68813, CVE-2025-68814, CVE-2025-68815, CVE-2025-68816, CVE-2025-68817, CVE-2025-68818, CVE-2025-68819, CVE-2025-68820, CVE-2025-68821, CVE-2025-68822, CVE-2025-68823, CVE-2025-71064, CVE-2025-71065, CVE-2025-71066, CVE-2025-71067, CVE-2025-71068, CVE-2025-71069, CVE-2025-71070, CVE-2025-71071, CVE-2025-71072, CVE-2025-71073, CVE-2025-71075, CVE-2025-71076, CVE-2025-71077, CVE-2025-71078, CVE-2025-71079, CVE-2025-71081, CVE-2025-71082, CVE-2025-71083, CVE-2025-71084, CVE-2025-71085, CVE-2025-71086, CVE-2025-71087, CVE-2025-71089, CVE-2025-71091, CVE-2025-71093, CVE-2025-71094, CVE-2025-71095, CVE-2025-71096, CVE-2025-71097, CVE-2025-71098, CVE-2025-71099, CVE-2025-71100, CVE-2025-71101, CVE-2025-71102, CVE-2025-71104, CVE-2025-71105, CVE-2025-71107, CVE-2025-71108, CVE-2025-71109, CVE-2025-71111, CVE-2025-71112, CVE-2025-71113, CVE-2025-71114, CVE-2025-71115, CVE-2025-71116, CVE-2025-71117, CVE-2025-71118, CVE-2025-71119, CVE-2025-71120, CVE-2025-71121, CVE-2025-71122, CVE-2025-71123, CVE-2025-71124, CVE-2025-71125, CVE-2025-71126, CVE-2025-71130, CVE-2025-71131, CVE-2025-71132, CVE-2025-71133, CVE-2025-71135, CVE-2025-71136, CVE-2025-71137, CVE-2025-71138, CVE-2025-71140, CVE-2025-71143, CVE-2025-71146, CVE-2025-71147, CVE-2025-71148, CVE-2025-71149, CVE-2025-71150, CVE-2025-71151, CVE-2025-71153, CVE-2025-71154, CVE-2025-71156, CVE-2025-71157, CVE-2026-23091, CVE-2026-23209
• Notes: EntrySign and multiple kernel subsystems

USN-8180-4: Linux kernel (Azure FIPS) vulnerabilities

Ubuntu says several security issues were found in the Linux kernel, and the update covers many subsystems. The notice lists network, TLS, file system, and driver areas among the affected components.

• Published: 23 Apr 2026 10:16 GMT
• CVEs: CVE-2023-53421, CVE-2023-53520, CVE-2023-53662, CVE-2023-54207, CVE-2025-38057, CVE-2025-38125, CVE-2025-38232, CVE-2025-38408, CVE-2025-38591, CVE-2025-40149, CVE-2025-40164, CVE-2025-68211, CVE-2025-68340, CVE-2025-68365, CVE-2025-68725, CVE-2025-68817, CVE-2025-71162, CVE-2025-71163, CVE-2025-71185, CVE-2025-71186, CVE-2025-71188, CVE-2025-71190, CVE-2025-71191, CVE-2025-71194, CVE-2025-71196, CVE-2025-71197, CVE-2025-71199, CVE-2026-22997, CVE-2026-22998, CVE-2026-22999, CVE-2026-23001, CVE-2026-23003, CVE-2026-23011, CVE-2026-23026, CVE-2026-23033, CVE-2026-23037, CVE-2026-23038, CVE-2026-23049, CVE-2026-23056, CVE-2026-23058, CVE-2026-23061, CVE-2026-23063, CVE-2026-23064, CVE-2026-23071, CVE-2026-23073, CVE-2026-23075, CVE-2026-23076, CVE-2026-23078, CVE-2026-23080, CVE-2026-23083, CVE-2026-23084, CVE-2026-23085, CVE-2026-23087, CVE-2026-23089, CVE-2026-23090, CVE-2026-23091, CVE-2026-23093, CVE-2026-23095, CVE-2026-23096, CVE-2026-23097, CVE-2026-23098, CVE-2026-23099, CVE-2026-23101, CVE-2026-23103, CVE-2026-23105, CVE-2026-23108, CVE-2026-23119, CVE-2026-23120, CVE-2026-23121, CVE-2026-23124, CVE-2026-23125, CVE-2026-23128, CVE-2026-23133, CVE-2026-23145, CVE-2026-23146, CVE-2026-23150, CVE-2026-23164, CVE-2026-23167, CVE-2026-23170, CVE-2026-23209
• Notes: network, TLS, file system, and driver areas

USN-8203-1: Linux kernel (Oracle) vulnerabilities

Ubuntu says the kernel update covers a long list of subsystems, including networking, file systems, and drivers. The notice also includes the EntrySign issue affecting some AMD Zen processors.

• Published: 23 Apr 2026 09:52 GMT
• CVEs: CVE-2024-36347, CVE-2024-57795, CVE-2025-22022, CVE-2025-22111, CVE-2025-38022, CVE-2025-38234, CVE-2025-40164, CVE-2025-40325, CVE-2025-68206, CVE-2025-68254, CVE-2025-68255, CVE-2025-68256, CVE-2025-68257, CVE-2025-68258, CVE-2025-68259, CVE-2025-68261, CVE-2025-68263, CVE-2025-68264, CVE-2025-68265, CVE-2025-68266, CVE-2025-68291, CVE-2025-68325, CVE-2025-68332, CVE-2025-68335, CVE-2025-68336, CVE-2025-68337, CVE-2025-68344, CVE-2025-68345, CVE-2025-68346, CVE-2025-68347, CVE-2025-68349, CVE-2025-68354, CVE-2025-68362, CVE-2025-68363, CVE-2025-68364, CVE-2025-68366, CVE-2025-68367, CVE-2025-68369, CVE-2025-68371, CVE-2025-68372, CVE-2025-68374, CVE-2025-68378, CVE-2025-68379, CVE-2025-68380, CVE-2025-68724, CVE-2025-68727, CVE-2025-68728, CVE-2025-68732, CVE-2025-68733, CVE-2025-68740, CVE-2025-68741, CVE-2025-68742, CVE-2025-68744, CVE-2025-68746, CVE-2025-68753, CVE-2025-68755, CVE-2025-68756, CVE-2025-68757, CVE-2025-68758, CVE-2025-68759, CVE-2025-68763, CVE-2025-68764, CVE-2025-68765, CVE-2025-68766, CVE-2025-68767, CVE-2025-68769, CVE-2025-68770, CVE-2025-68771, CVE-2025-68772, CVE-2025-68773, CVE-2025-68774, CVE-2025-68775, CVE-2025-68776, CVE-2025-68777, CVE-2025-68778, CVE-2025-68780, CVE-2025-68782, CVE-2025-68783, CVE-2025-68785, CVE-2025-68786, CVE-2025-68787, CVE-2025-68788, CVE-2025-68794, CVE-2025-68795, CVE-2025-68796, CVE-2025-68797, CVE-2025-68798, CVE-2025-68799, CVE-2025-68800, CVE-2025-68801, CVE-2025-68804, CVE-2025-68806, CVE-2025-68808, CVE-2025-68809, CVE-2025-68810, CVE-2025-68811, CVE-2025-68813, CVE-2025-68814, CVE-2025-68815, CVE-2025-68816, CVE-2025-68817, CVE-2025-68818, CVE-2025-68819, CVE-2025-68820, CVE-2025-68821, CVE-2026-23060, CVE-2026-23074, CVE-2026-23111, CVE-2026-23209
• Notes: EntrySign and kernel subsystems

USN-8179-3: Linux kernel vulnerabilities

Ubuntu says the kernel update covers many subsystems, including networking, file systems, and drivers. The notice also includes the EntrySign issue affecting some AMD Zen processors.

• Published: 23 Apr 2026 09:41 GMT
• CVEs: CVE-2024-36347, CVE-2024-57795, CVE-2025-22022, CVE-2025-22111, CVE-2025-38022, CVE-2025-38234, CVE-2025-40164, CVE-2025-40325, CVE-2025-68206, CVE-2025-68254, CVE-2025-68255, CVE-2025-68256, CVE-2025-68257, CVE-2025-68258, CVE-2025-68259, CVE-2025-68261, CVE-2025-68263, CVE-2025-68264, CVE-2025-68265, CVE-2025-68266, CVE-2025-68291, CVE-2025-68325, CVE-2025-68332, CVE-2025-68335, CVE-2025-68336, CVE-2025-68337, CVE-2025-68344, CVE-2025-68345, CVE-2025-68346, CVE-2025-68347, CVE-2025-68349, CVE-2025-68354, CVE-2025-68362, CVE-2025-68363, CVE-2025-68364, CVE-2025-68366, CVE-2025-68367, CVE-2025-68369, CVE-2025-68371, CVE-2025-68372, CVE-2025-68374, CVE-2025-68378, CVE-2025-68379, CVE-2025-68380, CVE-2025-68724, CVE-2025-68727, CVE-2025-68728, CVE-2025-68732, CVE-2025-68733, CVE-2025-68740, CVE-2025-68741, CVE-2025-68742, CVE-2025-68744, CVE-2025-68746, CVE-2025-68753, CVE-2025-68755, CVE-2025-68756, CVE-2025-68757, CVE-2025-68758, CVE-2025-68759, CVE-2025-68763, CVE-2025-68764, CVE-2025-68765, CVE-2025-68766, CVE-2025-68767, CVE-2025-68769, CVE-2025-68770, CVE-2025-68771, CVE-2025-68772, CVE-2025-68773, CVE-2025-68774, CVE-2025-68775, CVE-2025-68776, CVE-2025-68777, CVE-2025-68778, CVE-2025-68780, CVE-2025-68782, CVE-2025-68783, CVE-2025-68785, CVE-2025-68786, CVE-2025-68787, CVE-2025-68788, CVE-2025-68794, CVE-2025-68795, CVE-2025-68796, CVE-2025-68797, CVE-2025-68798, CVE-2025-68799, CVE-2025-68800, CVE-2025-68801, CVE-2025-68804, CVE-2025-68806, CVE-2025-68808, CVE-2025-68809, CVE-2025-68810, CVE-2025-68811, CVE-2025-68813, CVE-2025-68814, CVE-2025-68815, CVE-2025-68816, CVE-2025-68817, CVE-2025-68818, CVE-2025-68819, CVE-2025-68820, CVE-2025-68821, CVE-2026-23060, CVE-2026-23074, CVE-2026-23111, CVE-2026-23209
• Notes: kernel subsystems and EntrySign

Ubuntu

USN-8206-1: OpenMPT vulnerability

Ubuntu says OpenMPT did not properly limit the length of strings in certain cases, which led to a buffer overflow. The notice says an attacker could use this to crash OpenMPT and cause a denial of service.

• Published: 23 Apr 2026 16:05 GMT
• CVEs: Not stated in the advisory excerpt
• Notes: buffer overflow in certain cases

USN-8180-3: Linux kernel vulnerabilities

Ubuntu says several security issues were found in the Linux kernel, and the update corrects flaws across many subsystems. The notice lists networking, TLS, file systems, and driver areas among the affected components.

• Published: 23 Apr 2026 10:08 GMT
• CVEs: CVE-2023-53421, CVE-2023-53520, CVE-2023-53662, CVE-2023-54207, CVE-2025-38057, CVE-2025-38125, CVE-2025-38232, CVE-2025-38408, CVE-2025-38591, CVE-2025-40149, CVE-2025-40164, CVE-2025-68211, CVE-2025-68340, CVE-2025-68365, CVE-2025-68725, CVE-2025-68817, CVE-2025-71162, CVE-2025-71163, CVE-2025-71185, CVE-2025-71186, CVE-2025-71188, CVE-2025-71190, CVE-2025-71191, CVE-2025-71194, CVE-2025-71196, CVE-2025-71197, CVE-2025-71199, CVE-2026-22997, CVE-2026-22998, CVE-2026-22999, CVE-2026-23001, CVE-2026-23003, CVE-2026-23011, CVE-2026-23026, CVE-2026-23033, CVE-2026-23037, CVE-2026-23038, CVE-2026-23049, CVE-2026-23056, CVE-2026-23058, CVE-2026-23061, CVE-2026-23063, CVE-2026-23064, CVE-2026-23071, CVE-2026-23073, CVE-2026-23075, CVE-2026-23076, CVE-2026-23078, CVE-2026-23080, CVE-2026-23083, CVE-2026-23084, CVE-2026-23085, CVE-2026-23087, CVE-2026-23089, CVE-2026-23090, CVE-2026-23091, CVE-2026-23093, CVE-2026-23095, CVE-2026-23096, CVE-2026-23097, CVE-2026-23098, CVE-2026-23099, CVE-2026-23101, CVE-2026-23103, CVE-2026-23105, CVE-2026-23108, CVE-2026-23119, CVE-2026-23120, CVE-2026-23121, CVE-2026-23124, CVE-2026-23125, CVE-2026-23128, CVE-2026-23133, CVE-2026-23145, CVE-2026-23146, CVE-2026-23150, CVE-2026-23164, CVE-2026-23167, CVE-2026-23170, CVE-2026-23209
• Notes: networking, TLS, file systems, and drivers

Ubuntu

USN-8180-4: Linux kernel (Azure FIPS) vulnerabilities

Ubuntu says several security issues were found in the Linux kernel, and the update corrects flaws across many subsystems. The notice lists networking, TLS, file systems, and driver areas among the affected components.

• Published: 23 Apr 2026 10:16 GMT
• CVEs: CVE-2023-53421, CVE-2023-53520, CVE-2023-53662, CVE-2023-54207, CVE-2025-38057, CVE-2025-38125, CVE-2025-38232, CVE-2025-38408, CVE-2025-38591, CVE-2025-40149, CVE-2025-40164, CVE-2025-68211, CVE-2025-68340, CVE-2025-68365, CVE-2025-68725, CVE-2025-68817, CVE-2025-71162, CVE-2025-71163, CVE-2025-71185, CVE-2025-71186, CVE-2025-71188, CVE-2025-71190, CVE-2025-71191, CVE-2025-71194, CVE-2025-71196, CVE-2025-71197, CVE-2025-71199, CVE-2026-22997, CVE-2026-22998, CVE-2026-22999, CVE-2026-23001, CVE-2026-23003, CVE-2026-23011, CVE-2026-23026, CVE-2026-23033, CVE-2026-23037, CVE-2026-23038, CVE-2026-23049, CVE-2026-23056, CVE-2026-23058, CVE-2026-23061, CVE-2026-23063, CVE-2026-23064, CVE-2026-23071, CVE-2026-23073, CVE-2026-23075, CVE-2026-23076, CVE-2026-23078, CVE-2026-23080, CVE-2026-23083, CVE-2026-23084, CVE-2026-23085, CVE-2026-23087, CVE-2026-23089, CVE-2026-23090, CVE-2026-23091, CVE-2026-23093, CVE-2026-23095, CVE-2026-23096, CVE-2026-23097, CVE-2026-23098, CVE-2026-23099, CVE-2026-23101, CVE-2026-23103, CVE-2026-23105, CVE-2026-23108, CVE-2026-23119, CVE-2026-23120, CVE-2026-23121, CVE-2026-23124, CVE-2026-23125, CVE-2026-23128, CVE-2026-23133, CVE-2026-23145, CVE-2026-23146, CVE-2026-23150, CVE-2026-23164, CVE-2026-23167, CVE-2026-23170, CVE-2026-23209
• Notes: networking, TLS, file systems, and drivers

Ubuntu

USN-8183-2: Linux kernel vulnerabilities

Ubuntu says several security issues were found in the Linux kernel, and the update covers many subsystems. The notice also includes the EntrySign issue affecting some AMD Zen processors.

• Published: 23 Apr 2026 09:27 GMT
• CVEs: CVE-2024-36347, CVE-2025-68351, CVE-2025-68353, CVE-2025-68365, CVE-2025-68368, CVE-2025-68725, CVE-2025-68736, CVE-2025-68745, CVE-2025-68767, CVE-2025-68768, CVE-2025-68769, CVE-2025-68770, CVE-2025-68771, CVE-2025-68772, CVE-2025-68773, CVE-2025-68774, CVE-2025-68775, CVE-2025-68776, CVE-2025-68777, CVE-2025-68778, CVE-2025-68780, CVE-2025-68781, CVE-2025-68782, CVE-2025-68783, CVE-2025-68784, CVE-2025-68785, CVE-2025-68786, CVE-2025-68787, CVE-2025-68788, CVE-2025-68791, CVE-2025-68792, CVE-2025-68793, CVE-2025-68794, CVE-2025-68795, CVE-2025-68796, CVE-2025-68797, CVE-2025-68798, CVE-2025-68799, CVE-2025-68800, CVE-2025-68801, CVE-2025-68802, CVE-2025-68803, CVE-2025-68804, CVE-2025-68805, CVE-2025-68806, CVE-2025-68807, CVE-2025-68808, CVE-2025-68809, CVE-2025-68810, CVE-2025-68811, CVE-2025-68813, CVE-2025-68814, CVE-2025-68815, CVE-2025-68816, CVE-2025-68817, CVE-2025-68818, CVE-2025-68819, CVE-2025-68820, CVE-2025-68821, CVE-2025-68822, CVE-2025-68823, CVE-2025-71064, CVE-2025-71065, CVE-2025-71066, CVE-2025-71067, CVE-2025-71068, CVE-2025-71069, CVE-2025-71070, CVE-2025-71071, CVE-2025-71072, CVE-2025-71073, CVE-2025-71075, CVE-2025-71076, CVE-2025-71077, CVE-2025-71078, CVE-2025-71079, CVE-2025-71081, CVE-2025-71082, CVE-2025-71083, CVE-2025-71084, CVE-2025-71085, CVE-2025-71086, CVE-2025-71087, CVE-2025-71089, CVE-2025-71091, CVE-2025-71093, CVE-2025-71094, CVE-2025-71095, CVE-2025-71096, CVE-2025-71097, CVE-2025-71098, CVE-2025-71099, CVE-2025-71100, CVE-2025-71101, CVE-2025-71102, CVE-2025-71104, CVE-2025-71105, CVE-2025-71107, CVE-2025-71108, CVE-2025-71109, CVE-2025-71111, CVE-2025-71112, CVE-2025-71113, CVE-2025-71114, CVE-2025-71115, CVE-2025-71116, CVE-2025-71117, CVE-2025-71118, CVE-2025-71119, CVE-2025-71120, CVE-2025-71121, CVE-2025-71122, CVE-2025-71123, CVE-2025-71124, CVE-2025-71125, CVE-2025-71126, CVE-2025-71130, CVE-2025-71131, CVE-2025-71132, CVE-2025-71133, CVE-2025-71135, CVE-2025-71136, CVE-2025-71137, CVE-2025-71138, CVE-2025-71140, CVE-2025-71143, CVE-2025-71146, CVE-2025-71147, CVE-2025-71148, CVE-2025-71149, CVE-2025-71150, CVE-2025-71151, CVE-2025-71153, CVE-2025-71154, CVE-2025-71156, CVE-2025-71157, CVE-2026-23091, CVE-2026-23209
• Notes: EntrySign and kernel subsystems

More advisories

NIST

• CVE-2026-40575 — 22 Apr 2026 00:16 GMT