CVE-2025-37959: bpf: Scrub packet on bpf_redirect_peer

mediumCVSS 5.5CVE-2025-37959

CSIRTS triage

vendor: Linux product: Linux Kernel Denial of service

What: Packet metadata is not scrubbed during bpf_redirect_peer, allowing information leakage between network namespaces.
Who is affected: Systems using eBPF with bpf_redirect_peer between different network namespaces.
Urgency: Medium priority; information disclosure across namespace boundaries warrants patching.
Action: Update Linux kernel to include packet scrubbing in the bpf_redirect_peer code path.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 5.5
Published: 2026-08-06
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-37959

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2025-379590.30% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 23% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2025-37959	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

unknownexploitedSiemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFPcisa

Recent advisories for bpf

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

highCVE-2026-43009: bpf: Fix incorrect pruning due to atomic fetch precision trackingmsrc · 2026-08-06
mediumCVE-2024-47728: bpf: Zero former ARG_PTR_TO_{LONGINT} args in case of errormsrc · 2026-08-06
mediumCVE-2023-52920: bpf: support non-r10 register spill/fill to/from stack in precision trackingmsrc · 2026-08-06
highCVE-2026-45932: bpf: Fix tcx/netkit detach permissions when prog fd isn't givenmsrc · 2026-08-06
mediumCVE-2024-42151: bpf: mark bpf_dummy_struct_ops.test_1 parameter as nullablemsrc · 2026-08-06
mediumCVE-2026-23383: bpf, arm64: Force 8-byte alignment for JIT buffer to prevent atomic tearingmsrc · 2026-08-06