CVE Catalog

CVE-2026-64537

Low risk· EPSS 7%
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.17%

7th percentile - higher than 7% of all known CVEs

Summary

In the Linux kernel's bridge CFM module, the ccm_tx_work_expired() function is vulnerable to memory exhaustion (OOM). It re-arms itself with a 0 interval when exp_interval is invalid, leading to continuous buffer allocation and memory exhaustion.

Risk Assessment

An attacker can cause system memory exhaustion (OOM) by setting an invalid CCM interval in the bridge configuration, leading to system crash.

Recommendation

Apply the Linux kernel patch that constrains the valid exp_interval range in the netlink policy and rejects invalid values during configuration.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: bridge: cfm: reject invalid CCM interval at configuration time ccm_tx_work_expired() re-arms itself via queue_delayed_work() using the configured exp_interval converted by interval_to_us(). When exp_interval is BR_CFM_CCM_INTERVAL_NONE or out of range, interval_to_us() returns 0, causing the worker to fire immediately in a tight loop that allocates skbs until OOM. Fix this by validating exp_interval at configuration time: - Constrain IFLA_BRIDGE_CFM_CC_CONFIG_EXP_INTERVAL to the valid range [BR_CFM_CCM_INTERVAL_3_3_MS, BR_CFM_CCM_INTERVAL_10_MIN] in the netlink policy so userspace cannot set an invalid value. - Reject starting CCM TX in br_cfm_cc_ccm_tx() when exp_interval has not yet been configured (defaults to 0 from kzalloc).

Vulnerability data from NVD (NIST) · CISA KEV · EPSS