# CVE-2021-3449: OpenSSL: CVE-2021-3449 NULL pointer deref in signature_algorithms processing

CVE-2021-3449 is fixed in 27 products on 1 platform, first by libecpg-compat3 10.18-0ubuntu0.18.04.1, released March 24, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-3449
- Priority: Routine
- CVSS: 5.9 (Important)
- EPSS: 0.6354
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Less Likely
- Published: Mar 24, 2021
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-3449

## Description

An OpenSSL TLS server may crash if sent a maliciously crafted renegotiationClientHello message from a client. If a TLSv1.2 renegotiation ClientHelloomits the signature_algorithms extension (where it was present in theinitial ClientHello), but includes a signature_algorithms_cert extensionthen a NULL pointer dereference will result, leading to a crash and adenial of service attack. A server is only vulnerable if it has TLSv1.2 andrenegotiation enabled (which is the default configuration). OpenSSL TLSclients are not impacted by this issue. All OpenSSL 1.1.1 versions areaffected by this issue. Users of these versions should upgrade to OpenSSL1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL1.1.1k (Affected 1.1.1-1.1.1j).

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | libecpg-compat3 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [libecpg-compat3 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libecpg-compat3-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | libecpg-compat3 Ubuntu 20.04 LTS (focal) | 12.8-0ubuntu0.20.04.1 | [libecpg-compat3 12.8-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libecpg-compat3-12.8-0ubuntu0.20.04.1.md) | Aug 11, 2021 |
| Linux | libecpg6 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [libecpg6 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libecpg6-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | libecpg6 Ubuntu 20.04 LTS (focal) | 12.8-0ubuntu0.20.04.1 | [libecpg6 12.8-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libecpg6-12.8-0ubuntu0.20.04.1.md) | Aug 11, 2021 |
| Linux | libpgtypes3 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [libpgtypes3 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libpgtypes3-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | libpgtypes3 Ubuntu 20.04 LTS (focal) | 12.8-0ubuntu0.20.04.1 | [libpgtypes3 12.8-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libpgtypes3-12.8-0ubuntu0.20.04.1.md) | Aug 11, 2021 |
| Linux | libpq5 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [libpq5 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libpq5-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | libpq5 Ubuntu 20.04 LTS (focal) | 12.8-0ubuntu0.20.04.1 | [libpq5 12.8-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libpq5-12.8-0ubuntu0.20.04.1.md) | Aug 11, 2021 |
| Linux | libssl1.1 Ubuntu 18.04.6 LTS (bionic) | 1.1.1-1ubuntu2.1~18.04.9 | [libssl1.1 1.1.1-1ubuntu2.1~18.04.9](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libssl1.1-1.1.1-1ubuntu2.1-18.04.9.md) | Mar 24, 2021 |
| Linux | libssl1.1 Ubuntu 20.04 LTS (focal) | 1.1.1f-1ubuntu2.3 | [libssl1.1 1.1.1f-1ubuntu2.3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libssl1.1-1.1.1f-1ubuntu2.3.md) | Mar 24, 2021 |
| Linux | libssl3t64 Ubuntu 24.10 (oracular) | 1.1.1j-1ubuntu3 | [libssl3t64 1.1.1j-1ubuntu3](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-libssl3t64-1.1.1j-1ubuntu3.md) | Mar 25, 2021 |
| Linux | libssl3t64 Ubuntu 25.04 (plucky) | 1.1.1j-1ubuntu3 | [libssl3t64 1.1.1j-1ubuntu3](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-libssl3t64-1.1.1j-1ubuntu3.md) | Mar 25, 2021 |
| Linux | openssl RHEL 8 | 1:1.1.1g-15.el8_3 | [RHSA-2021:1024](https://patchblox.com/security/data/fix/linux/rhsa-2021-1024.md) | Mar 30, 2021 |
| Linux | openssl Ubuntu 18.04.6 LTS (bionic) | 1.1.1-1ubuntu2.1~18.04.9 | [openssl 1.1.1-1ubuntu2.1~18.04.9](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-openssl-1.1.1-1ubuntu2.1-18.04.9.md) | Mar 24, 2021 |
| Linux | openssl Ubuntu 20.04 LTS (focal) | 1.1.1f-1ubuntu2.3 | [openssl 1.1.1f-1ubuntu2.3](https://patchblox.com/security/data/fix/linux/ubuntu-focal-openssl-1.1.1f-1ubuntu2.3.md) | Mar 24, 2021 |
| Linux | openssl Ubuntu 24.10 (oracular) | 1.1.1j-1ubuntu3 | [openssl 1.1.1j-1ubuntu3](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-openssl-1.1.1j-1ubuntu3.md) | Mar 25, 2021 |
| Linux | openssl Ubuntu 25.04 (plucky) | 1.1.1j-1ubuntu3 | [openssl 1.1.1j-1ubuntu3](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-openssl-1.1.1j-1ubuntu3.md) | Mar 25, 2021 |
| Linux | openssl ol 8 | 2:1.1.1g-15.ksplice1.el8_3 | [ELSA-2021-9151](https://patchblox.com/security/data/fix/linux/elsa-2021-9151.md) | Apr 1, 2021 |
| Linux | openssl-debugsource ol 8 | 2:1.1.1g-15.ksplice1.el8_3 | [ELSA-2021-9151](https://patchblox.com/security/data/fix/linux/elsa-2021-9151.md) | Apr 1, 2021 |
| Linux | openssl-devel RHEL 8 | 1:1.1.1g-15.el8_3 | [RHSA-2021:1024](https://patchblox.com/security/data/fix/linux/rhsa-2021-1024.md) | Mar 30, 2021 |
| Linux | openssl-devel ol 8 | 2:1.1.1g-15.ksplice1.el8_3 | [ELSA-2021-9151](https://patchblox.com/security/data/fix/linux/elsa-2021-9151.md) | Apr 1, 2021 |
| Linux | openssl-libs RHEL 8 | 1:1.1.1g-15.el8_3 | [RHSA-2021:1024](https://patchblox.com/security/data/fix/linux/rhsa-2021-1024.md) | Mar 30, 2021 |
| Linux | openssl-libs ol 8 | 2:1.1.1g-15.ksplice1.el8_3 | [ELSA-2021-9151](https://patchblox.com/security/data/fix/linux/elsa-2021-9151.md) | Apr 1, 2021 |
| Linux | openssl-perl RHEL 8 | 1:1.1.1g-15.el8_3 | [RHSA-2021:1024](https://patchblox.com/security/data/fix/linux/rhsa-2021-1024.md) | Mar 30, 2021 |
| Linux | openssl-perl ol 8 | 2:1.1.1g-15.ksplice1.el8_3 | [ELSA-2021-9151](https://patchblox.com/security/data/fix/linux/elsa-2021-9151.md) | Apr 1, 2021 |
| Linux | openssl-static ol 8 | 2:1.1.1g-15.ksplice1.el8_3 | [ELSA-2021-9151](https://patchblox.com/security/data/fix/linux/elsa-2021-9151.md) | Apr 1, 2021 |
| Linux | postgresql-10 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [postgresql-10 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-postgresql-10-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | postgresql-12 Ubuntu 20.04 LTS (focal) | 12.8-0ubuntu0.20.04.1 | [postgresql-12 12.8-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-postgresql-12-12.8-0ubuntu0.20.04.1.md) | Aug 11, 2021 |
| Linux | postgresql-client-10 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [postgresql-client-10 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-postgresql-client-10-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | postgresql-client-12 Ubuntu 20.04 LTS (focal) | 12.8-0ubuntu0.20.04.1 | [postgresql-client-12 12.8-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-postgresql-client-12-12.8-0ubuntu0.20.04.1.md) | Aug 11, 2021 |
| Linux | postgresql-doc-10 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [postgresql-doc-10 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-postgresql-doc-10-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | postgresql-doc-12 Ubuntu 20.04 LTS (focal) | 12.8-0ubuntu0.20.04.1 | [postgresql-doc-12 12.8-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-postgresql-doc-12-12.8-0ubuntu0.20.04.1.md) | Aug 11, 2021 |
| Linux | postgresql-plperl-10 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [postgresql-plperl-10 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-postgresql-plperl-10-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | postgresql-plperl-12 Ubuntu 20.04 LTS (focal) | 12.8-0ubuntu0.20.04.1 | [postgresql-plperl-12 12.8-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-postgresql-plperl-12-12.8-0ubuntu0.20.04.1.md) | Aug 11, 2021 |
| Linux | postgresql-plpython-10 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [postgresql-plpython-10 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-postgresql-plpython-10-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | postgresql-plpython3-10 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [postgresql-plpython3-10 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-postgresql-plpython3-10-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | postgresql-plpython3-12 Ubuntu 20.04 LTS (focal) | 12.8-0ubuntu0.20.04.1 | [postgresql-plpython3-12 12.8-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-postgresql-plpython3-12-12.8-0ubuntu0.20.04.1.md) | Aug 11, 2021 |
| Linux | postgresql-pltcl-10 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [postgresql-pltcl-10 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-postgresql-pltcl-10-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | postgresql-pltcl-12 Ubuntu 20.04 LTS (focal) | 12.8-0ubuntu0.20.04.1 | [postgresql-pltcl-12 12.8-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-postgresql-pltcl-12-12.8-0ubuntu0.20.04.1.md) | Aug 11, 2021 |
| Linux | postgresql-server-dev-10 Ubuntu 18.04.6 LTS (bionic) | 10.18-0ubuntu0.18.04.1 | [postgresql-server-dev-10 10.18-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-postgresql-server-dev-10-10.18-0ubuntu0.18.04.1.md) | Mar 24, 2021 |
| Linux | postgresql-server-dev-12 Ubuntu 20.04 LTS (focal) | 12.8-0ubuntu0.20.04.1 | [postgresql-server-dev-12 12.8-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-postgresql-server-dev-12-12.8-0ubuntu0.20.04.1.md) | Aug 11, 2021 |

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