CVE-2022-49990: s390: fix double free of GS and RI CBs on fork() failure
Vulnerability summary
CVE-2022-49990 is a high (CVSS 7.8) Double Free vulnerability in linux. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 18.9% 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 8 · Related 7Timeline
- 18-06-2025PublishedVulnerability first disclosed.
- 15-10-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: s390: fix double free of GS and RI CBs on fork() failure The pointers for guarded storage and runtime instrumentation control blocks are stored in the thread_struct of the associated task. These pointers are initially copied on fork() via arch_dup_task_struct() and then cleared via copy_thread() before fork() returns. If fork() happens to fail after the initial task dup and before copy_thread(), the newly allocated task and associated thread_struct memory are freed via free_task() -> arch_release_task_struct(). This results in a double free of the guarded storage and runtime info structs because the fields in the failed task still refer to memory associated with the source task. This problem can manifest as a BUG_ON() in set_freepointer() (with CONFIG_SLAB_FREELIST_HARDENED enabled) or KASAN splat (if enabled) when running trinity syscall fuzz tests on s390x. To avoid this problem, clear the associated pointer fields in arch_dup_task_struct() immediately after the new task is copied. Note that the RI flag is still cleared in copy_thread() because it resides in thread stack memory and that is where stack info is copied.
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
0.27%
Chance of exploitation in the next 30 days
Percentile
19%
Versus all other CVEs
30-day change
Increase +0.01 pp
From 0.26% 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 causeAffected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu111 products
- linuxAll versions (No fix recorded) | < 4.15.0-201.212 | < 5.4.0-132.148 | < 5.15.0-53.59
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 4.15.0-1147.159 | < 5.4.0-1089.97 | < 5.15.0-1023.27
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 8d9047f8b967ce6181fd824ae922978e1b055cc0, < 25a95303b9e513cd2978aacc385d06e6fec23d07 | ≥ 8d9047f8b967ce6181fd824ae922978e1b055cc0, < cacd522e6652fbc2dc0cc6ae11c4e30782fef14b | ≥ 8d9047f8b967ce6181fd824ae922978e1b055cc0, < 297ae7e87a87a001dd3dfeac1cb26a42fd929708 | ≥ 8d9047f8b967ce6181fd824ae922978e1b055cc0, < 8195e065abf3df84eb0ad2987e76a40f21d1791c | ≥ 8d9047f8b967ce6181fd824ae922978e1b055cc0, < fbdc482d43eda40a70de4b0155843d5472f6de62 | ≥ 8d9047f8b967ce6181fd824ae922978e1b055cc0, < 13cccafe0edcd03bf1c841de8ab8a1c8e34f77d9 | 9e51ee1b76efc7b5e9404010793a39fde0e03cb7 | 232b47b3c88af1da737cd7760f247c4ed58168cf | b8e212c599082896a180a18a0c9bd529526590be | ≥ 4.4.105, < 4.5 | ≥ 4.9.68, < 4.10 | ≥ 4.14.5, < 4.15 | 4.15
- linux_kernel≥ 4.4.105, < 4.5 | ≥ 4.9.68, < 4.10 | ≥ 4.14.5, < 4.19.257 | ≥ 4.20, < 5.4.212 | ≥ 5.5, < 5.10.140 | ≥ 5.11, < 5.15.64 | ≥ 5.16, < 5.19.6 | 6.0:rc1 | 6.0:rc2
Debian1 product
- linux< 6.0.2-1
3 vendors · 114 products
