# CVE-2020-11945: squid: An issue was discovered in Squid before 5.0.2

CVE-2020-11945 is fixed in 8 products on 1 platform, first by squid 3.5.27-1ubuntu1.6, released April 23, 2020. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2020-11945
- Priority: High
- CVSS: 9.8 (Medium)
- EPSS: 0.2725
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Apr 23, 2020

## Description

An issue was discovered in Squid before 5.0.2. A remote attacker can replay a sniffed Digest Authentication nonce to gain access to resources that are otherwise forbidden. This occurs because the attacker can overflow the nonce reference counter (a short integer). Remote code execution may occur if the pooled token credentials are freed (instead of replayed as valid credentials).

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libecap RHEL 8 | 0:1.0.1-2.module+el8.1.0+4044+36416a77 | [RHSA-2020:2041](https://patchblox.com/security/data/fix/linux/rhsa-2020-2041.md) | May 6, 2020 |
| Linux | libecap ol 8 | 0:1.0.1-2.module+el8.1.0+5405+03b963f4 | [ELSA-2020-2041](https://patchblox.com/security/data/fix/linux/elsa-2020-2041.md) | May 12, 2020 |
| Linux | libecap-devel RHEL 8 | 0:1.0.1-2.module+el8.1.0+4044+36416a77 | [RHSA-2020:2041](https://patchblox.com/security/data/fix/linux/rhsa-2020-2041.md) | May 6, 2020 |
| Linux | libecap-devel ol 8 | 0:1.0.1-2.module+el8.1.0+5405+03b963f4 | [ELSA-2020-2041](https://patchblox.com/security/data/fix/linux/elsa-2020-2041.md) | May 12, 2020 |
| Linux | squid RHEL 8 | 7:4.4-8.module+el8.2.0+6449+6ba3df3e.1 | [RHSA-2020:2041](https://patchblox.com/security/data/fix/linux/rhsa-2020-2041.md) | May 6, 2020 |
| Linux | squid Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.6 | [squid 3.5.27-1ubuntu1.6](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squid-3.5.27-1ubuntu1.6.md) | Apr 23, 2020 |
| Linux | squid Ubuntu 20.04 LTS (focal) | 4.10-1ubuntu1.1 | [squid 4.10-1ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-squid-4.10-1ubuntu1.1.md) | Apr 23, 2020 |
| Linux | squid ol 8 | 7:4.4-8.module+el8.2.0+7611+d512f060.1 | [ELSA-2020-2041](https://patchblox.com/security/data/fix/linux/elsa-2020-2041.md) | May 12, 2020 |
| Linux | squid-cgi Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.6 | [squid-cgi 3.5.27-1ubuntu1.6](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squid-cgi-3.5.27-1ubuntu1.6.md) | Apr 23, 2020 |
| Linux | squid-cgi Ubuntu 20.04 LTS (focal) | 4.10-1ubuntu1.1 | [squid-cgi 4.10-1ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-squid-cgi-4.10-1ubuntu1.1.md) | Apr 23, 2020 |
| Linux | squid-common Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.6 | [squid-common 3.5.27-1ubuntu1.6](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squid-common-3.5.27-1ubuntu1.6.md) | Apr 23, 2020 |
| Linux | squid-common Ubuntu 20.04 LTS (focal) | 4.10-1ubuntu1.1 | [squid-common 4.10-1ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-squid-common-4.10-1ubuntu1.1.md) | Apr 23, 2020 |
| Linux | squid-purge Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.6 | [squid-purge 3.5.27-1ubuntu1.6](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squid-purge-3.5.27-1ubuntu1.6.md) | Apr 23, 2020 |
| Linux | squid-purge Ubuntu 20.04 LTS (focal) | 4.10-1ubuntu1.1 | [squid-purge 4.10-1ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-squid-purge-4.10-1ubuntu1.1.md) | Apr 23, 2020 |
| Linux | squid3 Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.6 | [squid3 3.5.27-1ubuntu1.6](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squid3-3.5.27-1ubuntu1.6.md) | Apr 23, 2020 |
| Linux | squidclient Ubuntu 18.04.6 LTS (bionic) | 3.5.27-1ubuntu1.6 | [squidclient 3.5.27-1ubuntu1.6](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-squidclient-3.5.27-1ubuntu1.6.md) | Apr 23, 2020 |
| Linux | squidclient Ubuntu 20.04 LTS (focal) | 4.10-1ubuntu1.1 | [squidclient 4.10-1ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-squidclient-4.10-1ubuntu1.1.md) | Apr 23, 2020 |

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