CVE-2023-49208VulnerabilityPublished 23 Nov 2023Updated 5 Jun 2025

CVE-2023-49208: n/a

Source CVE Database V5

Not known to be exploited · CVSS 9.8 Critical : upgrade to 2.7.6 as a priority.

Data as of 26 Oct 2026, 07:57 UTC

CVSS 3.1 base score

9.8Critical

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.8% chance of exploitation in 30 days – higher than 58% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 2.7.6

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 23 Nov 2023
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 2026-10-26.

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.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC 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 babelouest/glewlwyd to 2.7.6.

Affected software

Product	Affected	Fixed in
GitHubbabelouest/glewlwyd`pkg:github/babelouest/glewlwyd`Other threats	Affected <2.7.6	Fixed in 2.7.6

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

To mitigate the risks posed by CVE-2023-49208, European organizations should take immediate and specific actions beyond generic advice: 1) Identify and inventory all Glewlwyd SSO server deployments within the environment, including versions in use. 3) Implement network-level protections such as firewall rules and segmentation to limit exposure of the SSO server to untrusted sources. 4) Monitor logs and network traffic for unusual activity related to WebAuthn registration attempts or buffer overflow indicators. 5) Conduct thorough security assessments and penetration testing focused on the SSO infrastructure to detect potential exploitation attempts. 6) Prepare incident response plans specifically addressing potential compromise of authentication infrastructure. 7) Engage with the Glewlwyd community or maintainers to stay informed about patches and advisories. These steps will help reduce the attack surface and improve detection and response capabilities.

Description

scheme/webauthn.c in Glewlwyd SSO server before 2.7.6 has a possible buffer overflow during FIDO2 credentials validation in webauthn registration.

Impact

For European organizations, the impact of CVE-2023-49208 could be severe. Glewlwyd SSO servers are used to centralize authentication, often integrating with various internal and cloud services. A successful exploit could allow attackers to bypass authentication controls, gain unauthorized access to sensitive systems, and potentially move laterally within the network. This could lead to data breaches involving personal data protected under GDPR, intellectual property theft, disruption of business operations, and damage to organizational reputation. The critical nature of the vulnerability means that even organizations with strong perimeter defenses could be at risk if the SSO server is exposed to the internet or accessible by untrusted networks. Additionally, the lack of required authentication or user interaction for exploitation increases the risk of automated attacks. European entities in sectors such as finance, healthcare, government, and critical infrastructure, which often rely on robust authentication mechanisms, may face heightened risk due to the potential for cascading security failures following compromise of the SSO server.

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #11
The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output 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
Docker Security (opens in a new tab)
XML Security (opens in a new tab)
OWASP ASVS 4.0.3
V5.4.1 (opens in a new tab)
V14.1.2 (opens in a new tab)
V13.3.1 (opens in a new tab)
Attack patterns
Buffer Overflow via Environment Variables (opens in a new tab)
Overflow Buffers (opens in a new tab)
Client-side Injection-induced Buffer Overflow (opens in a new tab)
Filter Failure through Buffer Overflow (opens in a new tab)
MIME Conversion (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 7 Jul 2025, 16:11 UTC

WeaknessesCWE-120

Technical details

References

Community reviews

Related threats