CVE-2026-23444
CVE-2026-23444 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-401.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- EPSS exploit prediction: 0% (3rd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-18688
- Weakness: CWE-401
- Affected product: Linux Linux Kernel
- Published:
- Last modified:
Description
In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure ieee80211_tx_prepare_skb() has three error paths, but only two of them free the skb. The first error path (ieee80211_tx_prepare() returning TX_DROP) does not free it, while invoke_tx_handlers() failure and the fragmentation check both do. Add kfree_skb() to the first error path so all three are consistent, and remove the now-redundant frees in callers (ath9k, mt76, mac80211_hwsim) to avoid double-free. Document the skb ownership guarantee in the function's kdoc.
Frequently asked questions
- What is CVE-2026-23444?
- In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure ieee80211_tx_prepare_skb() has three error paths, but only two of them free the skb. The first error path (ieee80211_tx_prepare() returning TX_DROP) does not free it, while invoke_tx_handlers() failure and the fragmentation check both do. Add kfree_skb() to the first error path so all three are consistent, and remove the now-redundant frees in callers (ath9k, mt76, mac80211_hwsim) to avoid double-free. Document the skb ownership guarantee in the function's kdoc.
- How severe is CVE-2026-23444?
- CVE-2026-23444 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-23444 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-23444?
- CVE-2026-23444 primarily affects Linux Linux Kernel. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2026-23444?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-23444 have an EU (EUVD) identifier?
- Yes. CVE-2026-23444 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-18688.
- When was CVE-2026-23444 published?
- CVE-2026-23444 was published on 2026-04-03 and last updated on 2026-06-17.
References
- https://git.kernel.org/stable/c/06e769dddcbeb3baf2ce346273b53dd61fdbecf4
- https://git.kernel.org/stable/c/3b4d27acafaeab478fd24f79ad6e593a892828b9
- https://git.kernel.org/stable/c/50f1b690b4868923fbd242298def2fb88662f108
- https://git.kernel.org/stable/c/5ef8ca1c164786da24169af155c1ca1ff1353cf8
- https://git.kernel.org/stable/c/905ef207d5ed99ca64adfe39fba9ac46e434327a
- https://git.kernel.org/stable/c/9a779d1f480e83720b5384adf165604e7ee226bd
- https://git.kernel.org/stable/c/d5ad6ab61cbd89afdb60881f6274f74328af3ee9
- https://git.kernel.org/stable/c/f77b51bcee7be2bb686b5f7a2d4a1921e4bdb9f4
Affected products (9)
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:3.13:-:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*
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