SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2023-52928

In the Linux kernel, the following vulnerability has been resolved: bpf: Skip invalid kfunc call in backtrack_insn The verifier skips invalid kfunc call in check_kfunc_call(), which would be captured in fixup_kfunc_call() if such insn is not eliminated…

MEDIUM 5.5EPSS 0.24%

Does this matter?

Lower severity and a low EPSS score (0.24%). Track it; it rarely justifies an emergency change on its own.

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Skip invalid kfunc call in backtrack_insn The verifier skips invalid kfunc call in check_kfunc_call(), which would be captured in fixup_kfunc_call() if such insn is not eliminated by dead code elimination. However, this can lead to the following warning in backtrack_insn(), also see [1]: ------------[ cut here ]------------ verifier backtracking bug WARNING: CPU: 6 PID: 8646 at kernel/bpf/verifier.c:2756 backtrack_insn kernel/bpf/verifier.c:2756 __mark_chain_precision kernel/bpf/verifier.c:3065 mark_chain_precision kernel/bpf/verifier.c:3165 adjust_reg_min_max_vals kernel/bpf/verifier.c:10715 check_alu_op kernel/bpf/verifier.c:10928 do_check kernel/bpf/verifier.c:13821 [inline] do_check_common kernel/bpf/verifier.c:16289 [...] So make backtracking conservative with this by returning ENOTSUPP. [1] https://lore.kernel.org/bpf/CACkBjsaXNceR8ZjkLG=dT3P=4A8SBsg0Z5h5PWLryF5=ghKq=g@mail.gmail.com/

CVSS 3.1
5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.24% probability · 16th percentile
CISA KEV
Not listed
Affected
linux/linux kernel
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.