# CVE-2021-39636: linux: In do_ipt_get_ctl and do_ipt_set_ctl of ip_tables.c, there is a possible way to leak kernel information due to uninit...

CVE-2021-39636 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-39636, released December 15, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-39636
- Priority: Routine
- CVSS: 4.4 (medium)
- EPSS: 0.0023
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 15, 2021

## Description

In do_ipt_get_ctl and do_ipt_set_ctl of ip_tables.c, there is a possible way to leak kernel information due to uninitialized data. This could lead to local information disclosure with system execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-120612905References: Upstream kernel

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 4.16.5-1 | [DEBIAN-CVE-2021-39636](https://patchblox.com/security/data/fix/linux/debian-cve-2021-39636.md) | Dec 15, 2021 |
| Linux | linux Debian 13.5 (trixie) | 4.16.5-1 | [DEBIAN-CVE-2021-39636](https://patchblox.com/security/data/fix/linux/debian-cve-2021-39636.md) | Dec 15, 2021 |
| Linux | linux Debian 14 | 4.16.5-1 | [DEBIAN-CVE-2021-39636](https://patchblox.com/security/data/fix/linux/debian-cve-2021-39636.md) | Dec 15, 2021 |

---

Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.