CVE-2021-3638: fedoraproject fedora Out-of-bounds Write
Vulnerability summary
CVE-2021-3638 is a medium (CVSS 6.5) Out-of-bounds Write vulnerability in fedoraproject fedora. EPSS estimates a 0.43% chance of exploitation in the next 30 days, higher than 37.1% of scored vulnerabilities. 1 public exploit is recorded.
Not severe (CVSS 6.5, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 7 · Related 6Timeline
- 03-03-2022PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
Description
An out-of-bounds memory access flaw was found in the ATI VGA device emulation of QEMU. This flaw occurs in the ati_2d_blt() routine while handling MMIO write operations when the guest provides invalid values for the destination display parameters. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated6.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
EPSS trend
Probability
0.43%
Chance of exploitation in the next 30 days
Percentile
37%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.43% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
1 foundExploit Reference (lists.nongnu.org)
Maturity: unknown
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Debian1 product
- qemu< 1:6.1+dfsg-6
Fedoraproject1 product
- fedoraEOL36 | 37
Qemu1 product
- qemu≥ 4.0.0, ≤ 6.1.0
Ubuntu1 product
- qemu< 1:4.2-3ubuntu6.28
4 vendors · 4 products
References
10 links- lists.nongnu.org/archive/html/qemu-devel/2021-09/msg01682.htmlREPORTExploitMailing ListPatchThird Party Advisory
- security.netapp.com/advisory/ntap-20220407-0003/Third Party Advisory
