CVE-2025-21864
March 13, 2025, 9:13 p.m.
5.5
Medium
Description
In the Linux kernel, the following vulnerability has been resolved:
tcp: drop secpath at the same time as we currently drop dst
Xiumei reported hitting the WARN in xfrm6_tunnel_net_exit while
running tests that boil down to:
- create a pair of netns
- run a basic TCP test over ipcomp6
- delete the pair of netns
The xfrm_state found on spi_byaddr was not deleted at the time we
delete the netns, because we still have a reference on it. This
lingering reference comes from a secpath (which holds a ref on the
xfrm_state), which is still attached to an skb. This skb is not
leaked, it ends up on sk_receive_queue and then gets defer-free'd by
skb_attempt_defer_free.
The problem happens when we defer freeing an skb (push it on one CPU's
defer_list), and don't flush that list before the netns is deleted. In
that case, we still have a reference on the xfrm_state that we don't
expect at this point.
We already drop the skb's dst in the TCP receive path when it's no
longer needed, so let's also drop the secpath. At this point,
tcp_filter has already called into the LSM hooks that may require the
secpath, so it should not be needed anymore. However, in some of those
places, the MPTCP extension has just been attached to the skb, so we
cannot simply drop all extensions.
Product(s) Impacted
| Vendor | Product | Versions |
|---|---|---|
| Linux |
|
|
Weaknesses
Common security weaknesses mapped to this vulnerability.
CWE-476
NULL Pointer Dereference
A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit.
*CPE(s)
Affected systems and software identified for this CVE.
| Type | Vendor | Product | Version | Update | Edition | Language | Software Edition | Target Software | Target Hardware | Other Information |
|---|---|---|---|---|---|---|---|---|---|---|
| o | linux | linux_kernel | / | / | / | / | / | / | / | / |
| o | linux | linux_kernel | / | / | / | / | / | / | / | / |
| o | linux | linux_kernel | / | / | / | / | / | / | / | / |
| o | linux | linux_kernel | / | / | / | / | / | / | / | / |
| o | linux | linux_kernel | 6.14 | rc1 | / | / | / | / | / | / |
| o | linux | linux_kernel | 6.14 | rc2 | / | / | / | / | / | / |
| o | linux | linux_kernel | 6.14 | rc3 | / | / | / | / | / | / |
References
Tags
CVSS Score
CVSS Data - 3.1
- Attack Vector: LOCAL
- Attack Complexity: LOW
- Privileges Required: LOW
- Scope: UNCHANGED
- Confidentiality Impact: NONE
- Integrity Impact: NONE
- Availability Impact: HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Timeline
Published: March 12, 2025, 10:15 a.m.
Last Modified: March 13, 2025, 9:13 p.m.
Last Modified: March 13, 2025, 9:13 p.m.
Status : Analyzed
CVE is currently being analyzed by NVD staff, this process results in association of reference link tags, CVSS scores, CWE association, and CPE applicability statements.
More infoSource
416baaa9-dc9f-4396-8d5f-8c081fb06d67
*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.