CVE-2022-4129
CVE-2022-4129 is a medium-severity vulnerability in Linux Layer 2 Tunneling Protocol with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-667.
Key facts
- Severity: Medium (CVSS 3.x base score 5.5)
- EPSS exploit prediction: 0% (7th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-667
- Affected product: Linux Layer 2 Tunneling Protocol
- Published:
- Last modified:
Description
A flaw was found in the Linux kernel's Layer 2 Tunneling Protocol (L2TP). A missing lock when clearing sk_user_data can lead to a race condition and NULL pointer dereference. A local user could use this flaw to potentially crash the system causing a denial of service.
Frequently asked questions
- What is CVE-2022-4129?
- A flaw was found in the Linux kernel's Layer 2 Tunneling Protocol (L2TP). A missing lock when clearing sk_user_data can lead to a race condition and NULL pointer dereference. A local user could use this flaw to potentially crash the system causing a denial of service.
- How severe is CVE-2022-4129?
- CVE-2022-4129 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2022-4129 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2022-4129?
- CVE-2022-4129 primarily affects Linux Layer 2 Tunneling Protocol. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2022-4129?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2022-4129 published?
- CVE-2022-4129 was published on 2022-11-28 and last updated on 2026-06-17.
References
- https://lists.debian.org/debian-lts-announce/2023/05/msg00005.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7X5SPXMXXFANDASPCKER2JIQO2F3UHCP/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AM5KFIE6JNZXHBA5A2KYDZAT3MEX2B67/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JOKXNIM2R4FQCDRQV67UMAY6EBC72QFG/
- https://lore.kernel.org/all/20221114191619.124659-1-jakub%40cloudflare.com/t
- https://lore.kernel.org/netdev/20221121085426.21315-1-jakub%40cloudflare.com/t
Affected products (4)
- cpe:2.3:a:linux:layer_2_tunneling_protocol:*:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*
Other CWE-667 (Improper Locking) vulnerabilities
- CVE-2020-12658 — Critical (CVSS 9.8): gssproxy (aka gss-proxy) before 0.8.3 does not unlock cond_mutex before pthread exit in gp_worker_main() in…
- CVE-2019-5886 — Critical (CVSS 9.8): An issue was discovered in ShopXO 1.2.0. In the application\install\controller\Index.php file, there is no validation…
- CVE-2026-43215 — High (CVSS 8.8): In the Linux kernel, the following vulnerability has been resolved: cifs: Fix locking usage for tcon fields We used…
- CVE-2026-31629 — High (CVSS 8.8): In the Linux kernel, the following vulnerability has been resolved: nfc: llcp: add missing return after LLCP_CLOSED…
- CVE-2020-15674 — High (CVSS 8.8): Mozilla developers reported memory safety bugs present in Firefox 80. Some of these bugs showed evidence of memory…
- CVE-2021-1622 — High (CVSS 8.6): A vulnerability in the Common Open Policy Service (COPS) of Cisco IOS XE Software for Cisco cBR-8 Converged Broadband…