CVE-2022-50650 — bpf: Fix reference state management for synchronous callbacks
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix reference state management for synchronous callbacks Currently, verifier verifies callback functions (sync and async) as if they will be executed once, (i.e. it explores execution state as if the function was being called once). The next insn to explore is set to start of subprog and the exit from nested frame is handled using curframe > 0 and prepare_func_exit. In case of async callback it uses a customized variant of push_stack simulating a kind of branch to set up custom state and execution context for the async callback. While this approach is simple and works when callback really will be executed only once, it is unsafe for all of our current helpers which are for_each style, i.e. they execute the callback multiple times. A callback releasing acquired references of the caller may do so multiple times, but currently verifier sees it as one call inside the frame, which then returns to caller. Hence, it thinks it released some reference that the cb e.g. got access through callback_ctx (register filled inside cb from spilled typed register on stack). Similarly, it may see that an acquire call is unpaired inside the callback, so the caller will copy the reference state of callback and then will have to release the register with new ref_obj_ids. But again, the callback may execute multiple times, but the verifier will only account for acquired references for a single symbolic execution of the callback, which will cause leaks. Note that for async callback case, things are different. While currently we have bpf_timer_set_callback which only executes it once, even for multiple executions it would be safe, as reference state is NULL and check_reference_leak would force program to release state before BPF_EXIT. The state is also unaffected by analysis for the caller frame. Hence async callback is safe. Since we want the reference state to be accessible, e.g. for pointers loaded from stack through callback_ctx's PTR_TO_STACK, we still have to copy caller's reference_state to callback's bpf_func_state, but we enforce that whatever references it adds to that reference_state has been released before it hits BPF_EXIT. This requires introducing a new callback_ref member in the reference state to distinguish between caller vs callee references. Hence, check_reference_leak now errors out if it sees we are in callback_fn and we have not released callback_ref refs. Since there can be multiple nested callbacks, like frame 0 -> cb1 -> cb2 etc. we need to also distinguish between whether this particular ref belongs to this callback frame or parent, and only error for our own, so we store state->frameno (which is always non-zero for callbacks). In short, callbacks can read parent reference_state, but cannot mutate it, to be able to use pointers acquired by the caller. They must only undo their changes (by releasing their own acquired_refs before BPF_EXIT) on top of caller reference_state before returning (at which point the caller and callback state will match anyway, so no need to copy it back to caller).
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux | ≥ 69c087ba6225b574afb6e505b72cb75242a3d844 and < 4ed5155043c97ac8912bcf67331df87c833fb067≥ 69c087ba6225b574afb6e505b72cb75242a3d844 and < caa176c0953cdfd5ce500fb517ce1ea924a8bc4c≥ 69c087ba6225b574afb6e505b72cb75242a3d844 and < aed931fd3b6e28f19cc140ff90aa5046ee2aa4e1≥ 69c087ba6225b574afb6e505b72cb75242a3d844 and < 9d9d00ac29d0ef7ce426964de46fa6b380357d0aversion 5.13 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.8 | CVSS 3.1 | High | 1.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67) EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.16%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- CVSS changed · 7.8
- Source status changed · → Deferred
- Record created in this database
- 2025
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
4 on the record
Elsewhere on this site
Related CVEs (same products)
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- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 6h
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
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Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2022-50650 is "bpf: Fix reference state management for synchronous callbacks", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.8 describes technical severity. EPSS 0.16% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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