Out-of-bounds Read in Microsoft Windows
CVE-2021-29964
A locally-installed hostile program could send `WM_COPYDATA` messages that Firefox would process incorrectly, leading to an out-of-bounds read. *This bug only affects Firefox on Windows. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 78.11, Firefox < 89, and Firefox ESR < 78.11.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H.
EPSS exploit prediction
EPSS: 0.008 (55.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 55.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: +0.000
Affected products
- Microsoft Windows
- Mozilla Firefox — versions unspecified
- Mozilla Firefox Esr — versions unspecified
- Mozilla Firefox Esr
- Mozilla Thunderbird — versions unspecified
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.mozilla.org/security/advisories/mfsa2021-26/ (Release Notes, Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2021-24/ (Release Notes, Vendor Advisory)
- www.mozilla.org/security/advisories/mfsa2021-23/ (Release Notes, Vendor Advisory)
- bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-29964?
- CVE-2021-29964 is a high-severity vulnerability in Microsoft Windows, classified under Out-of-bounds Read. CVSS score: 7.1/10. Published 2021-06-24.
- How severe is CVE-2021-29964?
- High severity. CVSS v3 base score is 7.1 out of 10.
- Is CVE-2021-29964 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.