CVE-2021-47291

Description

In the Linux kernel, the following vulnerability has been resolved: ipv6: fix another slab-out-of-bounds in fib6_nh_flush_exceptions While running the self-tests on a KASAN enabled kernel, I observed a slab-out-of-bounds splat very similar to the one reported in commit 821bbf79fe46 ("ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions"). We additionally need to take care of fib6_metrics initialization failure when the caller provides an nh. The fix is similar, explicitly free the route instead of calling fib6_info_release on a half-initialized object.

CVSS Metrics

• v3.1•HIGH•Score: 7.1CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

EPSS Trends

Current EPSS score: 0.02%• Percentile: 4%

Techniques & Countermeasures

• CWE-125•Out-of-bounds Read

  The product reads data past the end, or before the beginning, of the intended buffer.

Affected Systems

• linux•linux

  ≥ f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74, < 830251361425c5be044db4d826aaf304ea3d14c6 | ≥ f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74, < ce8fafb68051fba52546f8bbe8621f7641683680 | ≥ f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74, < 115784bcccf135c3a3548098153413d76f16aae0 | ≥ f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74, < 8fb4792f091e608a0a1d353dfdf07ef55a719db5 | 5.3

• linux•linux_kernel

  ≥ 5.3, < 5.4.136 | ≥ 5.5, < 5.10.54 | ≥ 5.11, < 5.13.6 | 5.14:rc1 | 5.14:rc2

References (4)

• https://git.kernel.org/stable/c/830251361425c5be044db4d826aaf304ea3d14c6
• https://git.kernel.org/stable/c/ce8fafb68051fba52546f8bbe8621f7641683680
• https://git.kernel.org/stable/c/115784bcccf135c3a3548098153413d76f16aae0
• https://git.kernel.org/stable/c/8fb4792f091e608a0a1d353dfdf07ef55a719db5