CVE-2026-91954 (GCVE-0-2026-91954)
Vulnerability from cvelistv5 – Published: 2026-09-15 15:18 – Updated: 2026-09-15 15:18
VLAI
EPSS
VEX
Title
FreeRDP before 3.31.0 NULL Pointer Dereference via NSCodec
Summary
FreeRDP before 3.31.0 contains a null pointer dereference vulnerability in gdi_surface_bits when processing Surface Bits commands with NSCodec codec ID. A malicious RDP server can crash a FreeRDP client by sending a crafted Surface Bits command claiming to use NSCodec, even when the codec is disabled.
Severity
CWE
- CWE-476 - NULL Pointer Dereference
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/FreeRDP/FreeRDP/security/advis… | vendor-advisory |
| https://www.vulncheck.com/advisories/freerdp-befo… | third-party-advisory |
Impacted products
Date Public
2026-09-01 00:00
{
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},
{
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}
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"metrics": [
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"baseScore": 7.1,
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"userInteraction": "REQUIRED",
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"problemTypes": [
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"description": "NULL Pointer Dereference",
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"providerMetadata": {
"dateUpdated": "2026-09-15T15:18:10.550Z",
"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
"shortName": "VulnCheck"
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"references": [
{
"name": "GitHub Security Advisory (GHSA-ffjr-p229-hpch)",
"tags": [
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],
"url": "https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-ffjr-p229-hpch"
},
{
"name": "VulnCheck Advisory: FreeRDP before 3.31.0 NULL Pointer Dereference via NSCodec",
"tags": [
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"url": "https://www.vulncheck.com/advisories/freerdp-before-3.31.0-null-pointer-dereference-via-nscodec"
}
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"title": "FreeRDP before 3.31.0 NULL Pointer Dereference via NSCodec",
"x_generator": {
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"cveMetadata": {
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"cveId": "CVE-2026-91954",
"datePublished": "2026-09-15T15:18:10.550Z",
"dateReserved": "2026-09-15T11:07:34.398Z",
"dateUpdated": "2026-09-15T15:18:10.550Z",
"state": "PUBLISHED"
},
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"vulnerability-lookup:meta": {
"epss": {
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"date": "2026-09-16",
"epss": "0.00346",
"percentile": "0.27989"
},
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"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-09-15T18:31:56+00:00",
"cve": "CVE-2026-91954",
"id": "CVE-2026-91954",
"initial_release_date": "2026-09-15T15:18:10.550000+00:00",
"product_status:known_affected": "31",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "FreeRDP: FreeRDP: Denial of Service via crafted Surface Bits command",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91954.json",
"version": "3"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
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.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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