CVE-2020-26262

Summary

CVECVE-2020-26262
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-01-13 19:15:00 UTC
Updated2023-11-07 03:20:00 UTC
DescriptionCoturn is free open source implementation of TURN and STUN Server. Coturn before version 4.5.2 by default does not allow peers to connect and relay packets to loopback addresses in the range of `127.x.x.x`. However, it was observed that when sending a `CONNECT` request with the `XOR-PEER-ADDRESS` value of `0.0.0.0`, a successful response was received and subsequently, `CONNECTIONBIND` also received a successful response. Coturn then is able to relay packets to the loopback interface. Additionally, when coturn is listening on IPv6, which is default, the loopback interface can also be reached by making use of either `[::1]` or `[::]` as the peer address. By using the address `0.0.0.0` as the peer address, a malicious user will be able to relay packets to the loopback interface, unless `--denied-peer-ip=0.0.0.0` (or similar) has been specified. Since the default configuration implies that loopback peers are not allowed, coturn administrators may choose to not set the `denied-peer-ip` setting. The issue patched in version 4.5.2. As a workaround the addresses in the address block `0.0.0.0/8`, `[::1]` and `[::]` should be denied by default unless `--allow-loopback-peers` has been specified.

Risk And Classification

Problem Types: CWE-682 | CWE-441

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Coturn Project Coturn All All All All
Application Coturn Project Coturn All All All All
Operating System Fedoraproject Fedora 32 All All All
Operating System Fedoraproject Fedora 33 All All All

References

ReferenceSourceLinkTags
Merge branch 'advisory-fix-1' CVE-2020-26262 · coturn/coturn@abfe1fd · GitHub MISC github.com Patch, Third Party Advisory
[SECURITY] Fedora 32 Update: coturn-4.5.2-1.fc32 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
[SECURITY] Fedora 33 Update: coturn-4.5.2-1.fc33 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[SECURITY] Fedora 33 Update: coturn-4.5.2-1.fc33 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
Loopback bypass by using 0.0.0.0, [::1] or [::] as the peer address · Advisory · coturn/coturn · GitHub CONFIRM github.com Exploit, Third Party Advisory
[SECURITY] Fedora 32 Update: coturn-4.5.2-1.fc32 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
coturn/ChangeLog at 57180ab60afcaeb13537e69ae8cb8aefd8f3f546 · coturn/coturn · GitHub MISC github.com Release Notes, Third Party Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 501539 Alpine Linux Security Update for coturn
  • 504653 Alpine Linux Security Update for coturn
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