CVE-2021-23999
high
CVSS v3
—
CVSS v4 NEW
—
VIR risk
8.0
Description
If a Blob URL was loaded through some unusual user interaction, it could have been loaded by the System Principal and granted additional privileges that should not be granted to web content. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.
Predictions
Exploit likelihood
20%
Patch ETA
—
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Arch Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Fixed | 78.10.0-1 |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 78.10.0esr-1 |
| sid | Fixed | 88.0-1 |
| forky | Fixed | 78.10.0esr-1 |
| bullseye | Fixed | 78.10.0esr-1 |
| bookworm | Fixed | 78.10.0esr-1 |
Red Hat Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| 8 | Fixed | — |
References
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.