# firefox 91.0+build2-0ubuntu0.18.04.1: firefox 91.0+build2-0ubuntu0.18.04.1 for Ubuntu 18.04.6 LTS (bionic)

firefox 91.0+build2-0ubuntu0.18.04.1, released August 10, 2021, fixes 10 CVEs in firefox. None of them is reported as exploited. Patch Radar priority: High. The product is no longer supported.

- Web page: https://patchblox.com/security/fix/linux/ubuntu-bionic-firefox-91.0-build2-0ubuntu0.18.04.1
- Platform: Linux
- Released: Aug 10, 2021
- Priority: High (Closes CVE-2021-29985, high severity)
- CVEs: 10, exploited: 0, on CISA KEV: 0

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [firefox](https://patchblox.com/security/data/product/linux/firefox.md) | Ubuntu 18.04.6 LTS (bionic) | 91.0+build2-0ubuntu0.18.04.1 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2021-29985](https://patchblox.com/security/data/cve/CVE-2021-29985.md) | High | Firefox ESR and 3 others: A use-after-free vulnerability in media channels could have led to memory corruption and a potentially… | 8.8 | 0.0145 |  |
| [CVE-2021-29980](https://patchblox.com/security/data/cve/CVE-2021-29980.md) | High | Firefox ESR and 3 others: Uninitialized memory in a canvas object could have caused an incorrect free() leading to memory corruption… | 8.8 | 0.0140 |  |
| [CVE-2021-29984](https://patchblox.com/security/data/cve/CVE-2021-29984.md) | High | Firefox ESR and 3 others: Instruction reordering resulted in a sequence of instructions that would cause an object to be incorrectly… | 8.8 | 0.0139 |  |
| [CVE-2021-29988](https://patchblox.com/security/data/cve/CVE-2021-29988.md) | High | Firefox ESR and 3 others: Firefox incorrectly treated an inline list-item element as a block element, resulting in an out of bounds… | 8.8 | 0.0138 |  |
| [CVE-2021-29989](https://patchblox.com/security/data/cve/CVE-2021-29989.md) | High | Firefox ESR and 3 others: Mozilla developers reported memory safety bugs present in Firefox 90 and Firefox ESR 78.12. | 8.8 | 0.0127 |  |
| [CVE-2021-29986](https://patchblox.com/security/data/cve/CVE-2021-29986.md) | High | firefox: ELSA-2021-3157: firefox security update (IMPORTANT) | 8.1 | 0.0126 |  |
| [CVE-2021-29981](https://patchblox.com/security/data/cve/CVE-2021-29981.md) | High | Firefox ESR and 3 others: An issue present in lowering/register allocation could have led to obscure but deterministic register… | 8.8 | 0.0101 |  |
| [CVE-2021-29990](https://patchblox.com/security/data/cve/CVE-2021-29990.md) | High | Firefox ESR and 1 other: Mozilla developers and community members reported memory safety bugs present in Firefox 90. | 8.8 | 0.0101 |  |
| [CVE-2021-29982](https://patchblox.com/security/data/cve/CVE-2021-29982.md) | Routine | Firefox ESR and 3 others: Due to incorrect JIT optimization, we incorrectly interpreted data from the wrong type of object, resulting… | 6.5 | 0.0112 |  |
| [CVE-2021-29987](https://patchblox.com/security/data/cve/CVE-2021-29987.md) | Routine | firefox: After requesting multiple permissions, and closing the first permission panel, subsequent permission panels will be d... | n/a | 0.0095 |  |

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Data as of 2026-11-12T19:57:06Z 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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