CVE-2021-47541net/mlx4_en: Fix an use-after-free bug in mlx4_en_try_alloc_resources()
- 7.8HighCVSS base score
- 0.29%Exploitation in 30 daysEPSS · top 78% 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/mlx4_en: Fix an use-after-free bug in mlx4_en_try_alloc_resources() In mlx4_en_try_alloc_resources(), mlx4_en_copy_priv() is called and tmp->tx_cq will be freed on the error path of mlx4_en_copy_priv(). After that mlx4_en_alloc_resources() is called and there is a dereference of &tmp->tx_cq[t][i] in mlx4_en_alloc_resources(), which could lead to a use after free problem on failure of mlx4_en_copy_priv(). Fix this bug by adding a check of mlx4_en_copy_priv() This bug was found by a static analyzer. The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs. Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug. Builds with CONFIG_MLX4_EN=m show no new warnings, and our static analyzer no longer warns about this code.
Timeline
ID reserved
By Linux
Published
- 2 years later
· 2 years 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
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.29% · top 78% of all CVEs (15 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected ec25bc04ed8e12947738468cbe2191f1529f9e39 – < be12572c5ddc8ad7453bada4eec8fa46967dc757
- affected ec25bc04ed8e12947738468cbe2191f1529f9e39 – < 676dc7d9b15bf8733233a2db1ec3f9091ab34275
- affected ec25bc04ed8e12947738468cbe2191f1529f9e39 – < e461a9816a1ac5b4aeb61621b817225b61e46a68
- affected ec25bc04ed8e12947738468cbe2191f1529f9e39 – < f1d43efa59f1edd3e7eca0e94559b4c6b1cd4e2b
- affected ec25bc04ed8e12947738468cbe2191f1529f9e39 – < 75917372eef0dbfb290ae45474314d35f97aea18
- affected ec25bc04ed8e12947738468cbe2191f1529f9e39 – < addad7643142f500080417dd7272f49b7a185570
- affected 4.7
- unaffected < 4.7
- unaffected 4.14.257 – ≤ 4.14.*
- unaffected 4.19.220 – ≤ 4.19.*
- unaffected 5.4.164 – ≤ 5.4.*
- unaffected 5.10.84 – ≤ 5.10.*
- unaffected 5.15.7 – ≤ 5.15.*
- unaffected 5.16 – ≤ *
References
References6
- https://git.kernel.org/stable/c/be12572c5ddc8ad7453bada4eec8fa46967dc757 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/676dc7d9b15bf8733233a2db1ec3f9091ab34275 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/e461a9816a1ac5b4aeb61621b817225b61e46a68 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/f1d43efa59f1edd3e7eca0e94559b4c6b1cd4e2b (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/75917372eef0dbfb290ae45474314d35f97aea18 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/addad7643142f500080417dd7272f49b7a185570 (opens in a new tab)x_transferred
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-2021-34543 (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)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2021-47541)Record last updated .