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
Published
2026-02-25T04:04:17Z
Modified
2026-08-12T15:32:07Z
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/ns_turn_ioaddr.c" do not check "IN6_IS_ADDR_V4MAPPED". "ioa_addr_is_loopback()" checks "127.x.x.x" (AF_INET) and "::1" (AF_INET6), but not "::ffff:127.0.0.1." "ioa_addr_is_zero()" checks "0.0.0.0" and "::", but not "::ffff:0.0.0.0." "addr_less_eq()" used by "ioa_addr_in_range()" for "denied-peer-ip" matching: when the range is AF_INET and the peer is AF_INET6, 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 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-284",
        "CWE-441"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27624.json"
}
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
Fixed
b80eb898ba26552600770162c26a8ae7f3661b0b
Database specific
Show details 
{
    "cpe": "cpe:2.3:a:coturn_project:coturn:*:*:*:*:*:*:*:*",
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "4.9.0"
        }
    ],
    "source": [
        "CPE_RANGE",
        "REFERENCES"
    ]
}

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
4.5.1.0
4.5.1.1
4.5.1.2
4.5.1.3
4.5.2
4.6.0
4.6.2
4.6.3
4.7.0
4.8.0
docker/4.*
docker/4.5.2-r0
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-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"
vanir_signatures 
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        "signature_version": "v1",
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]
vanir_signatures_modified 
"2026-08-12T15:32:07Z"