CVE-2026-68441net/sched: Handle TC_ACT_REDIRECT from qdisc filter chains
- —Not scoredno CVSS score yet
- 0.17%Exploitation in 30 daysEPSS · top 94% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: Handle TC_ACT_REDIRECT from qdisc filter chains When a TC filter attached to a qdisc filter chain returns TC_ACT_REDIRECT (ex: via an eBPF program calling bpf_redirect() or an act_bpf action), the redirect was silently lost i.e no qdisc classify function handled TC_ACT_REDIRECT, so the packet fell through the switch and was enqueued normally instead of being redirected. This has been broken since bpf_redirect() was introduced for TC in commit 27b29f63058d ("bpf: add bpf_redirect() helper"). We got lucky for a long time because bpf_net_context was a per-CPU variable that was always available. commit 401cb7dae813 ("net: Reference bpf_redirect_info via task_struct on PREEMPT_RT.") turned bpf_net_context into a task_struct member that is only set up by explicit callers. Without a caller setting it up, bpf_redirect() itself crashes with a NULL pointer dereference in bpf_net_ctx_get_ri(). However, even with bpf_net_context available, TC_ACT_REDIRECT from qdisc filter chains cannot be honored without adding skb_do_redirect() calls to every qdisc classify function, which would require changes across net/sched/. Isolate it to ebpf core where it belongs. Instead, add a tcf_classify_qdisc() inline helper in pkt_cls.h, as a wrapper around tcf_classify() for use by qdisc classify functions and tcf_qevent_handle(). When the classify verdict is TC_ACT_REDIRECT, the wrapper converts it to TC_ACT_SHOT, dropping the packet rather than letting it continue silently. Dropping is preferred over letting the packet through because the user immediately sees packet loss. Silently passing the packet through would hide the problem and leave the user wondering why their redirect is not working. The clsact fast path, tc_run() continues to call tcf_classify() directly and is unaffected: TC_ACT_REDIRECT is returned as-is and handled by sch_handle_egress/ingress() calling skb_do_redirect() as before.
Timeline
ID reserved
By Linux
- 13 days later
· 13 days later
Published
- 3 months later
· 3 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.17% · top 94% of all CVEs (14 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected 27b29f63058d26c6c1742f1993338280d5a41dc6 – < 06629ed4d0ecba55bc425eaea79974484fe0b414
- affected 27b29f63058d26c6c1742f1993338280d5a41dc6 – < 98ca831065c4d20baf97dc9e232777dc47a2b923
- affected 27b29f63058d26c6c1742f1993338280d5a41dc6 – < 636658e50b5c6a2c93413a9fa6d9da768dbfdaf2
- affected 27b29f63058d26c6c1742f1993338280d5a41dc6 – < 9cbad9c8125f5fe377c0800ab08f7196eab44456
- affected 27b29f63058d26c6c1742f1993338280d5a41dc6 – < c8fd74445e86f88096d2f6cf0f9e4d54d8ed1781
- affected 27b29f63058d26c6c1742f1993338280d5a41dc6 – < ec48b3be2c8595dd290be883dbd4fb8b2f9f5d5e
- affected 4.4
- unaffected < 4.4
- unaffected 6.1.191 – ≤ 6.1.*
- unaffected 6.6.160 – ≤ 6.6.*
- unaffected 6.12.114 – ≤ 6.12.*
- unaffected 6.18.57 – ≤ 6.18.*
- unaffected 7.1.6 – ≤ 7.1.*
- unaffected 7.2 – ≤ *
References
References6
- https://git.kernel.org/stable/c/06629ed4d0ecba55bc425eaea79974484fe0b414 (opens in a new tab)
- https://git.kernel.org/stable/c/98ca831065c4d20baf97dc9e232777dc47a2b923 (opens in a new tab)
- https://git.kernel.org/stable/c/636658e50b5c6a2c93413a9fa6d9da768dbfdaf2 (opens in a new tab)
- https://git.kernel.org/stable/c/9cbad9c8125f5fe377c0800ab08f7196eab44456 (opens in a new tab)
- https://git.kernel.org/stable/c/c8fd74445e86f88096d2f6cf0f9e4d54d8ed1781 (opens in a new tab)
- https://git.kernel.org/stable/c/ec48b3be2c8595dd290be883dbd4fb8b2f9f5d5e (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-57049 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
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[](https://cveledger.app/cve/CVE-2026-68441)Record last updated .