# RHSA-2022:0818: firefox security update

RHSA-2022:0818, released March 10, 2022, fixes 13 CVEs in firefox (version 0:91.7.0-3.el8_5). 2 of them are being exploited (CVE-2022-26485); 2 on CISA KEV. Patch Radar priority: Patch now.

- Web page: https://patchblox.com/security/fix/linux/rhsa-2022-0818
- Platform: Linux
- Released: Mar 10, 2022
- Priority: Patch now (Closes CVE-2022-26485, exploited (CISA KEV))
- CVEs: 13, exploited: 2, on CISA KEV: 2
- Vendor advisory: https://access.redhat.com/errata/RHSA-2022:0818

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [firefox](https://patchblox.com/security/data/product/linux/firefox.md) | RHEL 8 | 0:91.7.0-3.el8_5 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2022-26485](https://patchblox.com/security/data/cve/CVE-2022-26485.md) | Patch now | Mozilla Firefox Use-After-Free Vulnerability | 9.8 | 0.1426 | CISA KEV |
| [CVE-2022-26486](https://patchblox.com/security/data/cve/CVE-2022-26486.md) | Patch now | Mozilla Firefox Use-After-Free Vulnerability | 9.8 | 0.0236 | CISA KEV |
| [CVE-2022-26384](https://patchblox.com/security/data/cve/CVE-2022-26384.md) | Urgent | Mozilla Thunderbird and 4 others: Protection Mechanism Failure | 9.8 | 0.0097 |  |
| [CVE-2022-26381](https://patchblox.com/security/data/cve/CVE-2022-26381.md) | Urgent | Mozilla Thunderbird and 4 others: Use After Free | 9.8 | 0.0087 |  |
| [CVE-2022-26386](https://patchblox.com/security/data/cve/CVE-2022-26386.md) | Urgent | firefox: Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability.  This... | 9.8 | 0.0071 |  |
| [CVE-2022-26383](https://patchblox.com/security/data/cve/CVE-2022-26383.md) | Urgent | Mozilla Thunderbird and 4 others: User Interface (UI) Misrepresentation of Critical Information | 9.8 | 0.0070 |  |
| [CVE-2022-26387](https://patchblox.com/security/data/cve/CVE-2022-26387.md) | Urgent | Mozilla Thunderbird and 4 others: Time-of-check Time-of-use (TOCTOU) Race Condition | 9.8 | 0.0066 |  |
| [CVE-2022-25236](https://patchblox.com/security/data/cve/CVE-2022-25236.md) | High | libxmltok1: xmlparse.c in Expat (aka libexpat) before 2.4.5 allows attackers to insert namespace-separator characters into namesp... | 9.8 | 0.3527 |  |
| [CVE-2022-22822](https://patchblox.com/security/data/cve/CVE-2022-22822.md) | High | xul-ext-lightning: addBinding in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow. | 9.8 | 0.0548 |  |
| [CVE-2022-25235](https://patchblox.com/security/data/cve/CVE-2022-25235.md) | High | libxmltok1: xmltok_impl.c in Expat (aka libexpat) before 2.4.5 lacks certain validation of encoding, such as checks for whether a... | 9.8 | 0.0496 |  |
| [CVE-2022-25315](https://patchblox.com/security/data/cve/CVE-2022-25315.md) | High | expat: In Expat (aka libexpat) before 2.4.5, there is an integer overflow in storeRawNames. | 9.8 | 0.0482 |  |
| [CVE-2022-22823](https://patchblox.com/security/data/cve/CVE-2022-22823.md) | High | thunderbird-mozsymbols: build_model in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow. | 9.8 | 0.0387 |  |
| [CVE-2022-22824](https://patchblox.com/security/data/cve/CVE-2022-22824.md) | High | expat: defineAttribute in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow. | 9.8 | 0.0387 |  |

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Data as of 2026-11-07T06:34:28Z 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