CVE-2021-47294
netrom: Decrease sock refcount when sock timers expire
- Published
- Updated
- Reserved
- Assigned by
- Linux
Description
In the Linux kernel, the following vulnerability has been resolved: netrom: Decrease sock refcount when sock timers expire Commit 63346650c1a9 ("netrom: switch to sock timer API") switched to use sock timer API. It replaces mod_timer() by sk_reset_timer(), and del_timer() by sk_stop_timer(). Function sk_reset_timer() will increase the refcount of sock if it is called on an inactive timer, hence, in case the timer expires, we need to decrease the refcount ourselves in the handler, otherwise, the sock refcount will be unbalanced and the sock will never be freed.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Analyzed | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.28% · top 80% of all CVEs (6 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: Medium 5.5.
Weakness
Affected products
- affected ce29e8a259de767f7210d346ad2b031cb8ab2732 – < 853262355518cd1247515b74e83fabf038aa6c29
- affected baa9e32336bf6d0d74a7c3486d2a27feaf57cd5f – < a01634bf91f2b6c42583770eb6815fb6d1e251cf
- affected 0adf571fa34b27bd0b97b408cc0f0dc54b72f0eb – < 48866fd5c361ea417ed24b43fc2a7dc2f5b060ef
- affected 2c6b572458a9127e8070df13fa7f115c29ab1d92 – < 9619cc7d97c3aa8ed3cfd2b8678b74fb6d6c7950
- affected 63346650c1a94a92be61a57416ac88c0a47c4327 – < 25df44e90ff5959b5c24ad361b648504a7e39ef3
- affected 63346650c1a94a92be61a57416ac88c0a47c4327 – < 6811744bd0efb9e472cb15d066cdb460beb8cb8a
- affected 63346650c1a94a92be61a57416ac88c0a47c4327 – < bc1660206c3723c37ed4d622ad81781f1e987250
- affected 63346650c1a94a92be61a57416ac88c0a47c4327 – < 517a16b1a88bdb6b530f48d5d153478b2552d9a8
- affected f1d9a1f2ef6ff17293d21d5e6b80e04bea0cf508
- affected 519e8a22a454b1f1baa3a151b184fe51bc18e178
- affected 4.4.173 – < 4.4.277
- affected 4.9.155 – < 4.9.277
- affected 4.14.98 – < 4.14.241
- affected 4.19.20 – < 4.19.199
- affected 3.18.134 – < 3.19
- affected 4.20.7 – < 4.21
- affected 5.0
- unaffected < 5.0
- unaffected 4.4.277 – ≤ 4.4.*
- unaffected 4.9.277 – ≤ 4.9.*
- unaffected 4.14.241 – ≤ 4.14.*
- unaffected 4.19.199 – ≤ 4.19.*
- unaffected 5.4.136 – ≤ 5.4.*
- unaffected 5.10.54 – ≤ 5.10.*
- unaffected 5.13.6 – ≤ 5.13.*
- unaffected 5.14 – ≤ *
References (8)
- https://git.kernel.org/stable/c/853262355518cd1247515b74e83fabf038aa6c29 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/a01634bf91f2b6c42583770eb6815fb6d1e251cf (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/48866fd5c361ea417ed24b43fc2a7dc2f5b060ef (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/9619cc7d97c3aa8ed3cfd2b8678b74fb6d6c7950 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/25df44e90ff5959b5c24ad361b648504a7e39ef3 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/6811744bd0efb9e472cb15d066cdb460beb8cb8a (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/bc1660206c3723c37ed4d622ad81781f1e987250 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/517a16b1a88bdb6b530f48d5d153478b2552d9a8 (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)
- 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://trackcve.app/cve/CVE-2021-47294)Record last updated .