CVE-2026-22855VulnerabilityPublished 12 Mar 2026Updated 18 Aug 2026

Red Hat Security Advisory: freerdp security update

Affects Red Hat freerdpSource GCVE Database

Compare

Mentioned vulnerabilities

Not known to be exploited : upgrade Red Hat freerdp to 8.5 or 8.4 soon.

Data as of 30 Oct 2026, 06:59 UTC

Severity

High

Rated by Threat Radar · No CVSS score from NVD or the CNA

EPSS: 0.8% chance of exploitation in 30 days – higher than 59% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 8.5, 8.4

Exploitation evidence

Disclosed: evidence found.
CVE published 12 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade Red Hat freerdp to 8.5 or 8.4.

Affected software

Product	Affected	Fixed in
Red Hat Product Security Red Hat	Affected >=8.4 <8.4 >=8.4 <8.5	Fixed in 8.4 8.5

AI-suggested

Red Hat has released updated freerdp packages that address these vulnerabilities. Users of Red Hat Enterprise Linux 8.4 should apply the security update as described in the Red Hat advisory RHSA-2026:4439. Detailed instructions for applying the update are available at https://access.redhat.com/articles/11258. No additional mitigation steps are indicated by the vendor.

Description

Multiple heap and global buffer overflow vulnerabilities have been identified in FreeRDP, a free implementation of the Remote Desktop Protocol client. These vulnerabilities affect the xfreerdp client used to connect to various RDP servers. Red Hat has issued an important security advisory for Red Hat Enterprise Linux 8.4 addressing these issues with updated freerdp packages.

Impact

The vulnerabilities involve heap and global buffer overflows, which can lead to memory corruption. Such issues may allow an attacker to cause application crashes or potentially execute arbitrary code if exploited. The advisory rates the security impact as Important (high severity). There are no known exploits in the wild at the time of the advisory.

Summary

The security advisory addresses three vulnerabilities in FreeRDP: CVE-2026-22855 and CVE-2026-22859 are heap-buffer-overflow flaws, and CVE-2026-22858 is a global-buffer-overflow flaw. These vulnerabilities could potentially lead to memory corruption issues. The affected product is Red Hat Enterprise Linux 8.4, specifically the freerdp packages included in this distribution. Red Hat has released updated packages to fix these vulnerabilities as part of their Extended Life Cycle Long Life 8.4 and AUS 8.4 support streams.

CWE-125Out-of-bounds Read (opens in a new tab)
Base weaknessCWE Top 25 (2025): #8
The product reads data past the end, or before the beginning, of the intended buffer.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
Architecture and Design · Language Selection
Use a language that provides appropriate memory abstractions.
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
Attack patterns
Overread Buffers (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-787Out-of-bounds Write (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #5
The product writes data past the end, or before the beginning, of the intended buffer.
Requirements · Language Selection
Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Operation · Build and Compilation · Environment Hardening
Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index…
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 18 Aug 2026, 13:58 UTC

WeaknessesCWE-125, CWE-787

Technical details

References

Community reviews

Related threats