GHSA-9Q6X-42CW-M8JX
Vulnerability from github – Published: 2026-08-11 15:32 – Updated: 2026-08-11 15:32FreeRDP before 3.30.0 contains an out-of-bounds vulnerability in kerberos_DecryptMessage() (winpr/libwinpr/sspi/Kerberos/kerberos.c). The 16-bit EC (extra count) field of a peer-supplied GSS Wrap token (RFC 4121) is used directly in pointer arithmetic to locate the encrypted regions without being bounds-checked, while only RRC and the total buffer length are validated. A malicious peer (server or client) can supply a large EC value (up to 0xFFFF) during CredSSP/NLA authentication, moving the decrypt operation's base pointers past the end of the ~60-byte token buffer. Because the AES-CTS-HMAC enctypes decrypt in place before the HMAC integrity check, this results in an out-of-bounds read and in-place out-of-bounds write, potentially leading to information disclosure, memory corruption, or denial of service.
{
"affected": [],
"aliases": [
"CVE-2026-72745"
],
"database_specific": {
"cwe_ids": [
"CWE-122"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-11T13:19:05Z",
"severity": "HIGH"
},
"details": "FreeRDP before 3.30.0 contains an out-of-bounds vulnerability in kerberos_DecryptMessage() (winpr/libwinpr/sspi/Kerberos/kerberos.c). The 16-bit EC (extra count) field of a peer-supplied GSS Wrap token (RFC 4121) is used directly in pointer arithmetic to locate the encrypted regions without being bounds-checked, while only RRC and the total buffer length are validated. A malicious peer (server or client) can supply a large EC value (up to 0xFFFF) during CredSSP/NLA authentication, moving the decrypt operation\u0027s base pointers past the end of the ~60-byte token buffer. Because the AES-CTS-HMAC enctypes decrypt in place before the HMAC integrity check, this results in an out-of-bounds read and in-place out-of-bounds write, potentially leading to information disclosure, memory corruption, or denial of service.",
"id": "GHSA-9q6x-42cw-m8jx",
"modified": "2026-08-11T15:32:37Z",
"published": "2026-08-11T15:32:37Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vv64-95pc-vj9v"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72745"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/freerdp-before-out-of-bounds-read-via-kerberos-gss-wrap-token-ec"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.