CVE-2026-63626

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Source
https://cve.org/CVERecord?id=CVE-2026-63626
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63626.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-63626
Aliases
  • GHSA-pc66-j6r6-49x9
Downstream
Published
2026-10-14T18:26:16Z
Modified
2026-10-28T11:17:04Z
Severity
  • 8.8 (High) CVSS_V3 - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
Summary
Mongoose: ppp_handle_ipv6cp() uses attacker-controlled length without bounds check — OOB read and heap overflow (PPP/PPPoE, MG_ENABLE_IPV6)
Details

Mongoose is an embedded web server and network library. Prior to 7.23, ppp_handle_ipv6cp() in src/l2_ppp.c trusts the 16-bit IPv6CP len field without checking it against the received payload size. On a PPP or PPPoE link using MG_ENABLE_TCPIP and MG_ENABLE_IPV6, an unauthenticated adjacent peer can complete the required LCP exchange and send a short Configure-Request with an oversized length, causing ppp_tx_frame() to read beyond recv_queue.buf and write beyond tx.buf. The same length misuse can also expose adjacent heap bytes in a reply or hang the event loop through find_opt(). This issue is fixed in version 7.23.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-122",
        "CWE-125"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63626.json"
}
References

Affected packages

Git / github.com/cesanta/mongoose

Affected ranges

Type
GIT
Repo
https://github.com/cesanta/mongoose
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
02bdbb9ed6f0a8f7c42228c6e7cb35d748b60551
Fixed
751f14742dea934bec08a507ab1fecc3673d4903
Database specific
Show details 
{
    "extracted_events": [
        {
            "range": [
                {
                    "introduced": "0"
                },
                {
                    "fixed": "7.23"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StringRangeExpression"
        },
        {
            "range": [
                {
                    "fixed": "751f14742dea934bec08a507ab1fecc3673d4903"
                }
            ],
            "source": "REFERENCES_COMMIT"
        },
        {
            "original_tag": "7.23",
            "range": [
                {
                    "fixed": "02bdbb9ed6f0a8f7c42228c6e7cb35d748b60551"
                }
            ],
            "source": "REFERENCES_TAG"
        }
    ]
}

Affected versions

3.*
3.2
3.3
3.4
3.5
3.6
3.7
3.8
4.*
4.0
4.1
5.*
5.0
5.1
5.2
5.3
5.4
5.5
5.5_20140120
5.6
6.*
6.0
6.1
6.10
6.11
6.12
6.13
6.14
6.15
6.16
6.17
6.18
6.2
6.3
6.4
6.5
6.6
6.7
6.9
7.*
7.0
7.1
7.11
7.12
7.13
7.14
7.15
7.16
7.17
7.18
7.19
7.2
7.20
7.21
7.22
7.3
7.4
7.5
7.6
7.7
7.8

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63626.json"
vanir_signatures 
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vanir_signatures_modified 
"2026-10-28T11:17:04Z"