# CVE-2018-16869: libhogweed4: A Bleichenbacher type side-channel based padding oracle attack was found in the way nettle handles endian conversion...

CVE-2018-16869 is fixed in 3 products on 1 platform, first by libhogweed4 3.4.1-0ubuntu0.18.04.1, released June 9, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2018-16869
- Priority: Routine
- CVSS: n/a (Low)
- EPSS: 0.0150
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 3, 2018

## Description

A Bleichenbacher type side-channel based padding oracle attack was found in the way nettle handles endian conversion of RSA decrypted PKCS#1 v1.5 data. An attacker who is able to run a process on the same physical core as the victim process, could use this flaw extract plaintext or in some cases downgrade any TLS connections to a vulnerable server.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libhogweed4 Ubuntu 18.04.6 LTS (bionic) | 3.4.1-0ubuntu0.18.04.1 | [libhogweed4 3.4.1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libhogweed4-3.4.1-0ubuntu0.18.04.1.md) | Jun 9, 2021 |
| Linux | libnettle6 Ubuntu 18.04.6 LTS (bionic) | 3.4.1-0ubuntu0.18.04.1 | [libnettle6 3.4.1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libnettle6-3.4.1-0ubuntu0.18.04.1.md) | Jun 9, 2021 |
| Linux | nettle-bin Ubuntu 18.04.6 LTS (bionic) | 3.4.1-0ubuntu0.18.04.1 | [nettle-bin 3.4.1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-nettle-bin-3.4.1-0ubuntu0.18.04.1.md) | Jun 9, 2021 |

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