# CVE-2021-28041: openssh-sftp-server: ssh-agent in OpenSSH before 8.5 has a double free that may be relevant in a few less-common scenarios, such as uncons...

CVE-2021-28041 is fixed in 6 products on 1 platform, first by openssh-client 1:8.2p1-4ubuntu0.2, released March 5, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-28041
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0351
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 5, 2021

## Description

ssh-agent in OpenSSH before 8.5 has a double free that may be relevant in a few less-common scenarios, such as unconstrained agent-socket access on a legacy operating system, or the forwarding of an agent to an attacker-controlled host.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | openssh-client Ubuntu 20.04 LTS (focal) | 1:8.2p1-4ubuntu0.2 | [openssh-client 1:8.2p1-4ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-openssh-client-1-8.2p1-4ubuntu0.2.md) | Mar 5, 2021 |
| Linux | openssh-server Ubuntu 20.04 LTS (focal) | 1:8.2p1-4ubuntu0.2 | [openssh-server 1:8.2p1-4ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-openssh-server-1-8.2p1-4ubuntu0.2.md) | Mar 5, 2021 |
| Linux | openssh-sftp-server Ubuntu 20.04 LTS (focal) | 1:8.2p1-4ubuntu0.2 | [openssh-sftp-server 1:8.2p1-4ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-openssh-sftp-server-1-8.2p1-4ubuntu0.2.md) | Mar 5, 2021 |
| Linux | openssh-tests Ubuntu 20.04 LTS (focal) | 1:8.2p1-4ubuntu0.2 | [openssh-tests 1:8.2p1-4ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-openssh-tests-1-8.2p1-4ubuntu0.2.md) | Mar 5, 2021 |
| Linux | ssh Ubuntu 20.04 LTS (focal) | 1:8.2p1-4ubuntu0.2 | [ssh 1:8.2p1-4ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-ssh-1-8.2p1-4ubuntu0.2.md) | Mar 5, 2021 |
| Linux | ssh-askpass-gnome Ubuntu 20.04 LTS (focal) | 1:8.2p1-4ubuntu0.2 | [ssh-askpass-gnome 1:8.2p1-4ubuntu0.2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-ssh-askpass-gnome-1-8.2p1-4ubuntu0.2.md) | Mar 5, 2021 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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