CVE-2026-45891: Linux kernel · net: hns3: fix double free issue for tx spare buffer
Source GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 27 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
Description
In the Linux kernel, the following vulnerability has been resolved: net: hns3: fix double free issue for tx spare buffer In hns3_set_ringparam(), a temporary copy (tmp_rings) of the ring structure is created for rollback. However, the tx_spare pointer in the original ring handle is incorrectly left pointing to the old backup memory. Later, if memory allocation fails in hns3_init_all_ring() during the setup, the error path attempts to free all newly allocated rings. Since tx_spare contains a stale (non-NULL) pointer from the backup, it is mistaken for a newly allocated buffer and is erroneously freed, leading to a double-free of the backup memory. The root cause is that the tx_spare field was not cleared after its value was saved in tmp_rings, leaving a dangling pointer. Fix this by setting tx_spare to NULL in the original ring structure when the creation of the new `tx_spare` fails. This ensures the error cleanup path only frees genuinely newly allocated buffers.
References
- nvd.nist.gov/vuln/detail/CVE-2026-45891 (opens in a new tab)
- git.kernel.org/stable/c/43015461662d41dcfb3bb95fadd8a2a42ad8eacf (opens in a new tab)
- git.kernel.org/stable/c/6d2f142b1e4b203387a92519d9d2e34752a79dbb (opens in a new tab)
- git.kernel.org/stable/c/6dc10494cfe27b6f1e9adb7e293293ae39c50b7c (opens in a new tab)
- git.kernel.org/stable/c/c3659273860bed0c8e573b865e3769abc51225a8 (opens in a new tab)
- git.kernel.org/stable/c/d2c785733dfb853ea0b53984c75662a1af230a94 (opens in a new tab)
- git.kernel.org/stable/c/fb6a4c376d454b425555b1b0bda36e99f56ec307 (opens in a new tab)
- git.kernel.org/stable/c/fdbccddb7e7822016601829f95de4008e193f7bc (opens in a new tab)