CVE-2026-45891: linux Double Free
Vulnerability summary
CVE-2026-45891 is a high (CVSS 7.8) Double Free vulnerability in linux. EPSS estimates a 0.18% chance of exploitation in the next 30 days, higher than 6.7% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 36 · Related 36Timeline
- 27-05-2026PublishedVulnerability first disclosed.
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.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.18%
Chance of exploitation in the next 30 days
Percentile
7%
Versus all other CVEs
30-day change
+0.05 pp
From 0.13% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu145 products
- linux< 5.15.0-186.196 | < 6.8.0-134.134 | All versions (No fix recorded)
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 5.15.0-1112.119 | < 6.8.0-1060.63 | All versions (No fix recorded)
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 907676b130711fd1f627824559e92259db2061d1, < fb6a4c376d454b425555b1b0bda36e99f56ec307 | ≥ 907676b130711fd1f627824559e92259db2061d1, < 43015461662d41dcfb3bb95fadd8a2a42ad8eacf | ≥ 907676b130711fd1f627824559e92259db2061d1, < 6dc10494cfe27b6f1e9adb7e293293ae39c50b7c | ≥ 907676b130711fd1f627824559e92259db2061d1, < d2c785733dfb853ea0b53984c75662a1af230a94 | ≥ 907676b130711fd1f627824559e92259db2061d1, < fdbccddb7e7822016601829f95de4008e193f7bc | ≥ 907676b130711fd1f627824559e92259db2061d1, < c3659273860bed0c8e573b865e3769abc51225a8 | ≥ 907676b130711fd1f627824559e92259db2061d1, < 6d2f142b1e4b203387a92519d9d2e34752a79dbb | 5.14
- linux_kernel≥ 5.14, < 5.15.202 | ≥ 5.16, < 6.1.165 | ≥ 6.2, < 6.6.128 | ≥ 6.7, < 6.12.75 | ≥ 6.13, < 6.18.14 | ≥ 6.19, < 6.19.4
Debian1 product
- linux< 6.1.170-1 | < 6.12.85-1 | < 6.18.14-1
3 vendors · 148 products
