CVE-2021-23997
Due to unexpected data type conversions, a use-after-free could have occurred when interacting with the font cache. We presume that with enough effort this could have been exploited to run arbitrary
02 Description
Due to unexpected data type conversions, a use-after-free could have occurred when interacting with the font cache. We presume that with enough effort this could have been exploited to run arbitrary
03 Exploitation and scoring
- Exploitation
- Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
- SSVC decision
- Not assessed by CISA
- EPSS probability
- 0.81% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 56.6% of scored records. A rank, not a probability.
- NVD base score
- 8.8 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-06-17.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2021-06-24 13:25Z5 YR AGO
- Last updated
- 2024-08-03 19:14Z2 YR AGO
- Reserved
- 2021-01-13
- Assigning CNA
- mozilla
- Record state
- PUBLISHED
- Severity
- Not rated by the issuing CNA
- CNA CVSS vector
- Not published by the issuing CNA
- Weaknesses
- CWE-681Incorrect Conversion between Numeric TypesBase
- Data version
- 5.1
- Document digest
- 8553389a0d12f77bd578ce521923197ca9fe3fdf1d4090bb06b3086179121e90
05 Affected products
06 References
- www.mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2021-16/
- bugzilla.mozilla.orghttps://bugzilla.mozilla.org/show_bug.cgi?id=1701942
07 Fixed in
Arch Linux
- firefox Fixed in 88.0-1
Source: Arch Linux Security Tracker, the Arch Linux security team. Reformatted by exploit.cc.
Ubuntu 16.04 LTS
- firefox Fixed in 88.0+build2-0ubuntu0.16.04.1
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 18.04 LTS
- firefox Fixed in 88.0+build2-0ubuntu0.18.04.2
- mozjs38 No fix yet
- mozjs52 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 20.04 LTS
- firefox Fixed in 88.0+build2-0ubuntu0.20.04.1
- mozjs52 No fix yet
- mozjs68 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 22.04 LTS
- mozjs78 No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.