CVE-2026-98229
Description
A flaw was found in the Linux kernel's XFRM (IPsec) subsystem. During incoming packet processing, certain network receive paths can reset security context information before the system finishes handling the IPsec state. If that state is concurrently deleted, the kernel can dereference freed memory, leading to a use-after-free vulnerability. An attacker could exploit this issue during network traffic handling to cause a kernel crash and a Denial of Service (DoS).
Statement
A race in XFRM input processing can cause a use after free when secpath_reset drops the last reference to an xfrm_state while xfrm_input still uses that state. VTI and XFRM interface receive callbacks can reset the secpath before later reads of x type proto or x props family, and the XFRM_MAX_DEPTH drop path can expose a similar lifetime problem. A remote peer may reach the vulnerable receive path by sending traffic to a configured XFRM or IPsec tunnel while the related state is concurrently deleted or reset. For the CVSS the PR:L value is used because reliable remote triggering normally requires access as a valid IPsec peer or equivalent access to the configured tunnel path. AC:H is used because exploitation depends on a narrow race with state deletion and on a specific VTI or XFRM interface configuration. Impact is at least denial of service through a kernel crash. Reuse of the freed state memory may permit confidentiality or integrity impact in the worst case, although no reliable arbitrary write primitive is established by the available code. The issue is generally limited to systems that expose configured XFRM or IPsec tunnel processing and is not reachable on systems where these paths are not configured.
Mitigation
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4.7 | N/A | 7.8 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | High | N/A | Low |
| Privileges Required | Low | N/A | Low |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | High |
| Integrity Impact | None | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Memory
The use of previously freed memory may corrupt valid data, if the memory area in question has been allocated and used properly elsewhere.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
If chunk consolidation occurs after the use of previously freed data, the process may crash when invalid data is used as chunk information.
Confidentiality
Technical Impact: Read Memory
Read operations on freed memory can sometimes leak sensitive information instead of causing a crash
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
If malicious data is entered before chunk consolidation can take place, it may be possible to take advantage of a write-what-where primitive to execute arbitrary code. If the newly allocated data happens to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.
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