CVE Catalog

CVE-2026-72330

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.63%

47th percentile - higher than 47% of all known CVEs

Summary

In the Linux kernel's net/tls module, there is an issue in tls_sw_read_sock() that causes empty TLS application data records to block subsequent data records. Empty records (allowed in TLS 1.3) are not consumed, leading to an infinite loop and connection stall.

Risk Assessment

An attacker can send empty TLS records, causing a denial of service (DoS) on the connection, blocking further data processing.

Recommendation

Apply a Linux kernel update containing the fix that consumes empty data records in the read_sock() path.

Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: net/tls: Consume empty data records in tls_sw_read_sock() A peer may send a zero-length TLS application_data record; TLS 1.3 explicitly permits these as a traffic-analysis countermeasure (RFC 8446, Section 5.1). After decryption such a record has full_len == 0. tls_sw_read_sock() hands it to the read_actor, which has no payload to consume and returns zero. The loop treats a zero return as backpressure (used <= 0), requeues the skb at the head of rx_list, and stops. rx_list is serviced head-first on the next call, so the empty record is dequeued, fails the same way, and is requeued again; every later record on the connection is blocked behind it. tls_sw_recvmsg() does not stall on this: a zero-length data record copies nothing and falls through to consume_skb(). Mirror that in the read_sock() path by recognizing an empty data record before the actor runs, consuming it, and continuing.

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