CVE-2025-68118 — Potential Heap Out-of-Bounds Read in freerdp_certificate_data_hash_ via Unsafe _snprintf Usage
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.20.0, a vulnerability exists in FreeRDP’s certificate handling code on Windows platforms. The function `freerdp_certificate_data_hash_ uses` the Microsoft-specific `_snprintf` function to format certificate cache filenames without guaranteeing NUL termination when truncation occurs. According to Microsoft documentation, `_snprintf` does not append a terminating NUL byte if the formatted output exceeds the destination buffer size. If an attacker controls the hostname value (for example via server redirection or a crafted .rdp file), the resulting filename buffer may not be NUL-terminated. Subsequent string operations performed on this buffer may read beyond the allocated memory region, resulting in a heap-based out-of-bounds read. In default configurations, the connection is typically terminated before sensitive data can be meaningfully exposed, but unintended memory read or a client crash may still occur under certain conditions. Version 3.20.0 has a patch for the issue.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+2
- Technical severity (critical)+10
- Automatable exploitation (SSVC)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — github.com (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Freerdp Freerdp).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 6.6 | CVSS 4.0 | Medium | — | — | security-advisories@github.com via NIST National Vulnerability Database |
| 6.6 | CVSS 4.0 | Medium | — | — | GitHub_M via CVE Program (cve.org) e CISA ADP |
| 9.1 | CVSS 3.1 | Critical | 3.9 | 5.2 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.24%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · freerdp/freerdp
- SSVC assessment updated
- Record published
- Fix documented
- CVSS changed · 9.1
- Source status changed · → Analyzed
- Record created in this database
- 2025
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
2 on the record
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-110839 FreeRDP 3.3.0 before 3.32.0 Heap Out-of-Bounds Write via Grayscale JPEG Clipboard Data 1d
- High CVE-2026-110838 FreeRDP shadow before 3.32.0 Pre-Authentication Input Injection via Confirm Active bypass 1d
- Medium CVE-2026-110834 FreeRDP 2.0.0 before 3.32.0 Denial of Service via Serial IRP Null Handle 1d
- Medium CVE-2026-110835 FreeRDP 3.0.0 before 3.32.0 HTTP Header Injection via Proxy Routing Token 1d
- Medium CVE-2026-110833 FreeRDP before 3.32.0 Unbounded Memory Retention via RDPDR Proxy 1d
- Medium CVE-2026-110832 FreeRDP 2.0.0 before 3.32.0 Memory Exhaustion via DRDYNVC DATA_FIRST 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2025-68118 is "Potential Heap Out-of-Bounds Read in freerdp_certificate_data_hash_ via Unsafe _snprintf Usage", rated Critical. It affects Freerdp (Freerdp); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 9.1 describes technical severity. EPSS 0.24% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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