System hang via printk lock inversion
Published Feb 26, 2025 · Updated May 23, 2026
Improper locking in the Linux kernel TTY subsystem allows local users to hang the system by triggering an allocation failure in pty_write(). The function calls kmalloc() while holding tty_port->lock; an allocation-error printk() can acquire console_owner through a circular lock chain. Low-privileged local access and an allocation failure are required, and successful exploitation interrupts availability without disclosing or modifying data.
Summary
What happened
Improper locking in the Linux kernel TTY subsystem allows local users to hang the system by triggering an allocation failure in pty_write(). The function calls kmalloc() while holding tty_port->lock; an allocation-error printk() can acquire console_owner through a circular lock chain. Low-privileged local access and an allocation failure are required, and successful exploitation interrupts availability without disclosing or modifying data.
The record
- CVE
- CVE-2022-49441
- Published
- Feb 26, 2025
- Updated
- May 23, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-667, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Feb 26, 2025CVE publishedPublication date reported by the CVE source.
- May 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=3.18.118 <3.19
- Affected versionversion=4.14.60 <4.14.283
- Affected versionversion=4.17.12 <4.18
- Affected versionversion=4.18
- Affected versionversion=4.4.146 <4.5
- Affected versionversion=4.9.117 <4.9.318
- Affected versionversion=60c4e8db32815474bfaeabe888ebb14e698caea1
- Affected versionversion=6d9cd12792270773fab9e5a129daff328d61ef9e
- Affected versionversion=6dbfa9b5ae65063cd61dc7fa11332e00bb794d8b
- Affected versionversion=b6da31b2c07c46f2dcad1d86caa835227a16d9ff <04ee31678c128a6cc7bb057ea189a8624ba5a314
- Affected versionversion=b6da31b2c07c46f2dcad1d86caa835227a16d9ff <0bcf44903ef4df742dcada86ccaedd25374ffb50
- Affected versionversion=b6da31b2c07c46f2dcad1d86caa835227a16d9ff <18ca0d55e8639b911df8aae1b47598b13f9acded
- Affected versionversion=b6da31b2c07c46f2dcad1d86caa835227a16d9ff <3219ac364ac3d8d30771612a6010f1e0b7fa0a28
- Affected versionversion=b6da31b2c07c46f2dcad1d86caa835227a16d9ff <6b9dbedbe3499fef862c4dff5217cf91f34e43b3
- Affected versionversion=b6da31b2c07c46f2dcad1d86caa835227a16d9ff <9834b13e8b962caa28fbcf1f422dd82413da4ede
- Affected versionversion=b6da31b2c07c46f2dcad1d86caa835227a16d9ff <b3c974501d0c32258ae0e04e5cc3fb92383b40f6
- Affected versionversion=d83904cb2eb2c4d937eaf15032214b0578f25099 <4af21b12a60ed2d3642284f4f85b42d7dc6ac246
- Affected versionversion=deb1feaad03a78b545c949e54582ae57b3c56982 <4c253caf9264d2aa47ee806a87986dd8eb91a5d9
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo