openssh 8.7p1-38.1.el9_4.security.0.7

docs/issues/CVE-2024-6409.md

@@ -0,0 +1,29 @@
+# CVE-2024-6409: openssh
+
+## Title
+
+CVE-2024-6409: OpenSSH: Possible remote code execution in privsep child due to a race condition in signal handling
+
+## Summary
+
+As [discovered by Solar Designer (CIQ/Rocky Linux)](https://www.openwall.com/lists/oss-security/2024/07/08/2):
+
+OpenSSH versions 8.7 and 8.8 and the corresponding portable releases call `cleanup_exit()` from `grace_alarm_handler()` when running in the privsep child process. `cleanup_exit()` was not meant to be called from a signal handler and may call other async-signal-unsafe functions. The current understanding is that in those upstream versions `cleanup_exit()` would not actually call async-signal-unsafe functions under those conditions, but with downstream distribution patches it sometimes does. Specifically, openssh-7.6p1-audit.patch found in Red Hat's package of OpenSSH adds code to `cleanup_exit()` that exposes the issue. Relevantly, this patch is found in EL 9, where the package is based on OpenSSH 8.7p1.
+
+This is an EL9-specific issue similar to [CVE-2024-6387 regreSSHion](CVE-2024-6387.md).
+
+Public disclosure date: July 8, 2024
+
+## EL9
+
+- Fixed in version: `8.7p1-38.1.el9_4.security.0.7` available July 8, 2024
+
+## EL8
+
+- Unaffected
+
+## Mitigation
+
+Set `LoginGraceTime 0` in `/etc/ssh/sshd_config` and do a `systemctl restart sshd`.
+
+A drawback of this mitigation is that it will make the SSH server more susceptible to denial of service attacks.

docs/news.md

@@ -2,6 +2,11 @@
 
 These are what we consider significant SIG/Security news items, not an exhaustive list of package updates and wiki edits.
 
+## July 8, 2024
+
+[openssh](packages/openssh.md) `8.7p1-38.1.el9_4.security.0.7` for EL9 adds a fix for [CVE-2024-6409](issues/CVE-2024-6409.md),
+an EL9-specific issue similar to [CVE-2024-6387 regreSSHion](issues/CVE-2024-6387.md).
+
 ## July 1, 2024
 
 [openssh](packages/openssh.md) `8.7p1-38.el9_4.security.0.5` for EL9 adds a fix for [CVE-2024-6387 regreSSHion](issues/CVE-2024-6387.md).

docs/packages/openssh.md

@@ -2,18 +2,24 @@
 
 ## EL9
 
-- Version `8.7p1-38.el9_4.security.0.5`
+- Version `8.7p1-38.1.el9_4.security.0.7`
-- Based on `8.7p1-38.el9`
+- Based on `8.7p1-38.el9_4.1`
 
 ### Changes summary
 
 - Instead of linking against `libsystemd`, load it dynamically in a temporary child process to avoid polluting actual `sshd`'s address space with that library and its many dependencies (shortens `ldd sshd` output from 28 to 20 lines)
 - Build without Kerberos support (further shortens `ldd sshd` from 20 to 13 lines)
-- Fix CVE-2024-6387 regreSSHion
+- Fix [CVE-2024-6409](../issues/CVE-2024-6409.md)
 
 ### Change log
 
 ```
+* Mon Jul 08 2024 Solar Designer <solar@openwall.com> 8.7p1-38.1.el9_4.security.0.7
+- Fix CVE-2024-6409
+
+* Mon Jul 08 2024 Solar Designer <solar@openwall.com> 8.7p1-38.1.el9_4.security.0.6
+- Rebase on 8.7p1-38.1
+
 * Mon Jul 01 2024 Solar Designer <solar@openwall.com> 8.7p1-38.el9_4.security.0.5
 - Fix CVE-2024-6387 regreSSHion