CVE-2021-47060: KVM: Stop looking for coalesced MMIO zones if the bus is destroyed
Vulnerability summary
CVE-2021-47060 is a high (CVSS 7.8) vulnerability in linux. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 15.1% of scored vulnerabilities.
Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 6 · Related 6Timeline
- 29-02-2024PublishedVulnerability first disclosed.
- 05-08-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: KVM: Stop looking for coalesced MMIO zones if the bus is destroyed Abort the walk of coalesced MMIO zones if kvm_io_bus_unregister_dev() fails to allocate memory for the new instance of the bus. If it can't instantiate a new bus, unregister_dev() destroys all devices _except_ the target device. But, it doesn't tell the caller that it obliterated the bus and invoked the destructor for all devices that were on the bus. In the coalesced MMIO case, this can result in a deleted list entry dereference due to attempting to continue iterating on coalesced_zones after future entries (in the walk) have been deleted. Opportunistically add curly braces to the for-loop, which encompasses many lines but sneaks by without braces due to the guts being a single if statement.
CVSS metrics
5 scores · 4 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVDNIST7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.24%
Chance of exploitation in the next 30 days
Percentile
15%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.24% 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
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu86 products
- linuxAll versions (No fix recorded) | < 5.4.0-77.86
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 5.4.0-1051.53
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 41b2ea7a6a11e2b1a7f2c29e1675a709a6b2b98d, < 7d1bc32d6477ff96a32695ea4be8144e4513ab2d | ≥ f65886606c2d3b562716de030706dfe1bea4ed5e, < 2a20592baff59c5351c5200ec667e1a2aa22af85 | ≥ f65886606c2d3b562716de030706dfe1bea4ed5e, < 168e82f640ed1891a700bdb43e37da354b2ab63c | ≥ f65886606c2d3b562716de030706dfe1bea4ed5e, < 50cbad42bfea8c052b7ca590bd4126cdc898713c | ≥ f65886606c2d3b562716de030706dfe1bea4ed5e, < 5d3c4c79384af06e3c8e25b7770b6247496b4417 | f0dfffce3f4ffd5f822568a4a6fb34c010e939d1 | 840e124f89a5127e7eb97ebf377f4b8ca745c070 | 40a023f681befd9b2862a3c16fb306a38b359ae5 | 19184bd06f488af62924ff1747614a8cb284ad63 | 68c125324b5e1d1d22805653735442923d896a1d | ≥ 5.4.66, < 5.4.119 | ≥ 4.4.238, < 4.5 | ≥ 4.9.238, < 4.10 | ≥ 4.14.200, < 4.15 | ≥ 4.19.148, < 4.20 | ≥ 5.8.10, < 5.9 | 5.9
- linux_kernel≥ 5.4.66, < 5.4.119 | ≥ 5.9, < 5.10.37 | ≥ 5.11, < 5.11.21 | ≥ 5.12, < 5.12.4
Debian1 product
- linux< 5.10.38-1
3 vendors · 89 products
