CVE-2026-27624

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Source
https://cve.org/CVERecord?id=CVE-2026-27624
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-27624.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-27624
Downstream
Related
  • GHSA-6g6j-r9rf-cm7p
  • GHSA-j8mm-mpf8-gvjg
Published
2026-02-25T04:04:17.009Z
Modified
2026-03-03T02:56:40.903956Z
Severity
  • 7.2 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N CVSS Calculator
Summary
Coturn: IPv4-mapped IPv6 (::ffff:0:0/96) bypasses denied-peer-ip ACL
Details

Coturn is a free open source implementation of TURN and STUN Server. Coturn is commonly configured to block loopback and internal ranges using "denied-peer-ip" and/or default loopback restrictions. CVE-2020-26262 addressed bypasses involving "0.0.0.0", "[::1]" and "[::]", but IPv4-mapped IPv6 is not covered. When sending a "CreatePermission" or "ChannelBind" request with the "XOR-PEER-ADDRESS" value of "::ffff:127.0.0.1", a successful response is received, even though "127.0.0.0/8" is blocked via "denied-peer-ip". The root cause is that, prior to the updated fix implemented in version 4.9.0, three functions in "src/client/nsturnioaddr.c" do not check "IN6ISADDRV4MAPPED". "ioaaddrisloopback()" checks "127.x.x.x" (AFINET) and "::1" (AFINET6), but not "::ffff:127.0.0.1." "ioaaddriszero()" checks "0.0.0.0" and "::", but not "::ffff:0.0.0.0." "addrlesseq()" used by "ioaaddrinrange()" for "denied-peer-ip" matching: when the range is AFINET and the peer is AFINET6, the comparison returns 0 without extracting the embedded IPv4. Version 4.9.0 contains an updated fix to address the bypass of the fix for CVE-2020-26262.

Database specific 
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27624.json",
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-284",
        "CWE-441"
    ]
}
References

Affected packages

Git / github.com/coturn/coturn

Affected ranges

Type
GIT
Repo
https://github.com/coturn/coturn
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
41ba6d8f5d073ab27440ef061022eb88123fba62

Affected versions

4.*
4.4.5.3
4.4.5.4
4.5.0.1
4.5.0.2
4.5.0.3
4.5.0.4
4.5.0.5
4.5.0.6
4.5.0.7
4.5.0.8
4.5.1.0
4.5.1.1
4.5.1.2
4.5.1.3
4.5.2
4.6.0
4.6.1
4.6.2
4.6.3
4.7.0
4.8.0
docker/4.*
docker/4.5.2-r0
docker/4.5.2-r1
docker/4.5.2-r10
docker/4.5.2-r11
docker/4.5.2-r12
docker/4.5.2-r13
docker/4.5.2-r14
docker/4.5.2-r2
docker/4.5.2-r3
docker/4.5.2-r4
docker/4.5.2-r5
docker/4.5.2-r6
docker/4.5.2-r7
docker/4.5.2-r8
docker/4.5.2-r9
docker/4.6.0-r0
docker/4.6.0-r1
docker/4.6.1-r0
docker/4.6.1-r1
docker/4.6.1-r2
docker/4.6.1-r3
docker/4.6.2-r0
docker/4.6.2-r1
docker/4.6.2-r10
docker/4.6.2-r11
docker/4.6.2-r12
docker/4.6.2-r13
docker/4.6.2-r2
docker/4.6.2-r3
docker/4.6.2-r4
docker/4.6.2-r5
docker/4.6.2-r6
docker/4.6.2-r7
docker/4.6.2-r8
docker/4.6.2-r9
docker/4.6.3-r0
docker/4.6.3-r1
docker/4.6.3-r2
docker/4.6.3-r3
docker/4.7.0-r0
docker/4.7.0-r1
docker/4.7.0-r2
docker/4.7.0-r3
docker/4.7.0-r4
docker/4.8.0-r0
docker/4.8.0-r1

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-27624.json"