Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC PR UI S C I A CVSS EPSS %ile KEV L L L N U N N H 5.5 .0022 13.0 —
AFFECTED Product Versions Fixed Linux 3953ae7b218df4d1e544b98a393666f9ae58a78c – — Linux 4.15 – 6.11.3
TIMELINE Oct 21 Reserved by Linux Oct 21 Published (CNA: Linux) Aug 4 RESCORED — CVE-2024-49940 (Linux). CVSS 7.8 → 5.5 (NVD).
In the Linux kernel, the following vulnerability has been resolved: l2tp: prevent possible tunnel refcount underflow When a session is created, it sets a backpointer to its tunnel. When the session refcount drops to 0, l2tp_session_free drops the tunnel refcount if session->tunnel is non-NULL. However, session->tunnel is set in l2tp_session_create, before the tunnel refcount is incremented by l2tp_session_register, which leaves a small window where session->tunnel is non-NULL when the tunnel refcount hasn't been bumped. Moving the assignment to l2tp_session_register is trivial but l2tp_session_create calls l2tp_session_set_header_len which uses session->tunnel to get the tunnel's encap. Add an encap arg to l2tp_session_set_header_len to avoid using session->tunnel. If l2tpv3 sessions have colliding IDs, it is possible for l2tp_v3_session_get to race with l2tp_session_register and fetch a session which doesn't yet have session->tunnel set. Add a check for this case.
| Date | Event | Detail |
|---|---|---|
| October 21, 2024 | Reserved | Reserved by Linux |
| October 21, 2024 | Published | Published (CNA: Linux) |
| August 4, 2026 | RESCORED | RESCORED — CVE-2024-49940 (Linux). CVSS 7.8 → 5.5 (NVD). |
Authoritative record: CVE-2024-49940 at cve.org
Vendors: linux
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2024-49940 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.