CVE-2026-43074: eventpoll: defer struct eventpoll free to RCU grace period
Vulnerability summary
CVE-2026-43074 is a high (CVSS 7.8) vulnerability in linux. EPSS estimates a 0.48% chance of exploitation in the next 30 days, higher than 41.6% 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 46 · Related 39Timeline
- 06-05-2026PublishedVulnerability first disclosed.
- 19-10-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: eventpoll: defer struct eventpoll free to RCU grace period In certain situations, ep_free() in eventpoll.c will kfree the epi->ep eventpoll struct while it still being used by another concurrent thread. Defer the kfree() to an RCU callback to prevent UAF.
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
0.48%
Chance of exploitation in the next 30 days
Percentile
42%
Versus all other CVEs
30-day change
Increase +0.31 pp
From 0.18% 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 cause- CWE-401Missing Release of Memory after Effective LifetimeThe product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.
- CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
Affected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu142 products
- linux< 5.15.0-186.196 | < 6.8.0-136.136 | All versions (No fix recorded)
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 5.15.0-1112.119 | < 6.8.0-1061.64 | All versions (No fix recorded)
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ f2451def095c1743adcfcb0cb5dadc86034e162a, < 902120be4f44947df6311002addc7faf69bdbff1 | ≥ a1f93804449d13f97dabd4b996817de4bf1ed67a, < a6d57084372161f86660bc4607784420e00efe2c | ≥ 58c9b016e12855286370dfb704c08498edbc857a, < a6566cd33f6f967a7651ebf2ce0dd31572e319cf | ≥ 58c9b016e12855286370dfb704c08498edbc857a, < 5b1173b165421561db29f30afc7e97d940a398a9 | ≥ 58c9b016e12855286370dfb704c08498edbc857a, < 7e8083f5eeedab0f460063b9c2c14c9a4e71a427 | ≥ 58c9b016e12855286370dfb704c08498edbc857a, < ae0bb9c1fb7c2594519aeeb096cf2c3b7837b322 | ≥ 58c9b016e12855286370dfb704c08498edbc857a, < 07712db80857d5d09ae08f3df85a708ecfc3b61f | 6.4
- linux_kernelEOL≥ 6.4.1, < 6.6.136 | ≥ 6.7, < 6.12.83 | ≥ 6.13, < 6.18.24 | ≥ 6.19, < 6.19.14 | 6.4 | 7.0:rc1 | 7.0:rc2 | 7.0:rc3 | 7.0:rc4 | 7.0:rc5 | 7.0:rc6 | 7.0:rc7
Debian1 product
- linux< 6.12.85-1 | < 6.19.14-1
3 vendors · 145 products
