CVE-2026-31657
In the Linux kernel, the following vulnerability has been resolved: batman-adv: hold claim backbone gateways by reference batadv_bla_add_claim() can replace claim->backbone_gw and drop the old gateway's last reference while readers still follow the…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.40%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: batman-adv: hold claim backbone gateways by reference batadv_bla_add_claim() can replace claim->backbone_gw and drop the old gateway's last reference while readers still follow the pointer. The netlink claim dump path dereferences claim->backbone_gw->orig and takes claim->backbone_gw->crc_lock without pinning the underlying backbone gateway. batadv_bla_check_claim() still has the same naked pointer access pattern. Reuse batadv_bla_claim_get_backbone_gw() in both readers so they operate on a stable gateway reference until the read-side work is complete. This keeps the dump and claim-check paths aligned with the lifetime rules introduced for the other BLA claim readers.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.40% probability · 33th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/1f2dc36c297d27733f1b380ea644cf15a361bd7bPatch
- https://git.kernel.org/stable/c/2f55b58b5a0bbed192d60c444a45a49cdf1b545fPatch
- https://git.kernel.org/stable/c/4dee4c0688443aaf5bbec74aa203c851d1d53c35Patch
- https://git.kernel.org/stable/c/5202f071b367ffbc8e279fc7a00db14f5e587f52
- https://git.kernel.org/stable/c/69d1ce9c72eca91203ffdb8d08bacd511100aec6
- https://git.kernel.org/stable/c/7962b522222628596ca9ecc8722efc95367aadbdPatch
- https://git.kernel.org/stable/c/82d8701b2c930d0e96b0dbc9115a218d791cb0d2Patch
- https://git.kernel.org/stable/c/f4858832ddef2f39f21e30b7226bbcd3c4b2bc96Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.