# CVE-2020-8517: squid: An issue was discovered in Squid before 4.10

CVE-2020-8517 is fixed in 6 products on 1 platform, first by squid 3.5.27-1ubuntu1.5, released February 4, 2020. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-8517
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0685
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Feb 4, 2020

## Description

An issue was discovered in Squid before 4.10. Due to incorrect input validation, the NTLM authentication credentials parser in ext_lm_group_acl may write to memory outside the credentials buffer. On systems with memory access protections, this can result in the helper process being terminated unexpectedly. This leads to the Squid process also terminating and a denial of service for all clients using the proxy.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | squid Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.5 | [squid 3.5.27-1ubuntu1.5](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squid-3.5.27-1ubuntu1.5.md) | Feb 4, 2020 |
| Linux | squid Ubuntu 20.04 LTS (focal) | 4.9-2ubuntu4 | [squid 4.9-2ubuntu4](https://patchblox.com/security/data/fix/linux/ubuntu-focal-squid-4.9-2ubuntu4.md) | Feb 4, 2020 |
| Linux | squid-cgi Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.5 | [squid-cgi 3.5.27-1ubuntu1.5](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squid-cgi-3.5.27-1ubuntu1.5.md) | Feb 4, 2020 |
| Linux | squid-cgi Ubuntu 20.04 LTS (focal) | 4.9-2ubuntu4 | [squid-cgi 4.9-2ubuntu4](https://patchblox.com/security/data/fix/linux/ubuntu-focal-squid-cgi-4.9-2ubuntu4.md) | Feb 4, 2020 |
| Linux | squid-common Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.5 | [squid-common 3.5.27-1ubuntu1.5](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squid-common-3.5.27-1ubuntu1.5.md) | Feb 4, 2020 |
| Linux | squid-common Ubuntu 20.04 LTS (focal) | 4.9-2ubuntu4 | [squid-common 4.9-2ubuntu4](https://patchblox.com/security/data/fix/linux/ubuntu-focal-squid-common-4.9-2ubuntu4.md) | Feb 4, 2020 |
| Linux | squid-purge Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.5 | [squid-purge 3.5.27-1ubuntu1.5](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squid-purge-3.5.27-1ubuntu1.5.md) | Feb 4, 2020 |
| Linux | squid-purge Ubuntu 20.04 LTS (focal) | 4.9-2ubuntu4 | [squid-purge 4.9-2ubuntu4](https://patchblox.com/security/data/fix/linux/ubuntu-focal-squid-purge-4.9-2ubuntu4.md) | Feb 4, 2020 |
| Linux | squid3 Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.5 | [squid3 3.5.27-1ubuntu1.5](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squid3-3.5.27-1ubuntu1.5.md) | Feb 4, 2020 |
| Linux | squid3 Ubuntu 20.04 LTS (focal) | 4.9-2ubuntu4 | [squid3 4.9-2ubuntu4](https://patchblox.com/security/data/fix/linux/ubuntu-focal-squid3-4.9-2ubuntu4.md) | Feb 4, 2020 |
| Linux | squidclient Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.5 | [squidclient 3.5.27-1ubuntu1.5](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squidclient-3.5.27-1ubuntu1.5.md) | Feb 4, 2020 |
| Linux | squidclient Ubuntu 20.04 LTS (focal) | 4.9-2ubuntu4 | [squidclient 4.9-2ubuntu4](https://patchblox.com/security/data/fix/linux/ubuntu-focal-squidclient-4.9-2ubuntu4.md) | Feb 4, 2020 |

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