VulnerabilityPublished 13 Jun 2024Updated 2 Aug 2024

CVE-2024-37877: UERANSIM · Out-of-bounds Read

Affects UERANSIMSource CVE Database V5

Not known to be exploited · CVSS 5.5 Medium : upgrade to 3.2.6 when convenient.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

5.5Medium

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

EPSS: 0.3% chance of exploitation in 30 days – higher than 23% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 3.2.6

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: Required
Scope: Unchanged
Confidentiality: Low
Integrity: Low
Availability: Low

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: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
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: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 13 Jun 2024
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 26 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.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, 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 f4rs1ght/UERANSIM to 3.2.6.

Affected software

Product	Affected	Fixed in
GitHubf4rs1ght/UERANSIM`pkg:github/f4rs1ght/UERANSIM`Other threats	Affected <3.2.6	Fixed in 3.2.6

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

AI-suggested

Upgrade UERANSIM to version 3.2.6 or later as soon as the patch addressing CVE-2024-37877 becomes available.
Implement strict input validation and length checks on RLS packets within the network simulation environment to prevent malformed PDUs from triggering out-of-bounds reads.
Restrict network access to UERANSIM instances, especially the gNodeB interfaces, to trusted users and systems only, minimizing exposure to untrusted sources.
Monitor network traffic for anomalous or malformed RLS packets that could indicate attempted exploitation.
Employ runtime memory protection techniques such as AddressSanitizer or similar tools during testing to detect and mitigate out-of-bounds memory access.
Educate users and administrators about the risks of interacting with untrusted network inputs in simulation environments.
Maintain up-to-date backups and recovery plans for simulation data to mitigate potential availability impacts.
Collaborate with the UERANSIM development community to track vulnerability disclosures and patches promptly.

Description

UERANSIM before 3.2.6 allows out-of-bounds read when a RLS packet is sent to gNodeB with malformed PDU length. This occurs in function readOctetString in src/utils/octet_view.cpp and in function DecodeRlsMessage in src/lib/rls/rls_pdu.cpp

Impact

The primary impact of CVE-2024-37877 is an out-of-bounds read vulnerability that can lead to partial disclosure of memory contents, potentially exposing sensitive data processed by the UERANSIM gNodeB component. While the confidentiality impact is limited, attackers might leverage this information for further attacks or reconnaissance. Integrity and availability impacts are also low but possible, as malformed packets could cause application instability or crashes, affecting service continuity in simulated environments. Since UERANSIM is mainly used for 5G core network simulation and testing, the direct impact on production networks is limited; however, compromised test environments could lead to inaccurate testing results or delayed deployment of secure 5G infrastructure. The requirement for low privileges and user interaction reduces the likelihood of widespread exploitation but does not eliminate risk in controlled environments. Organizations relying on UERANSIM for research, development, or training could face operational disruptions and potential leakage of sensitive test data. The absence of known exploits reduces immediate risk but underscores the need for proactive mitigation.

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).

References

github.com/f4rs1ght/vuln-research/tree/main/CVE-2024-37877 (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 28 Feb 2026, 03:52 UTC

WeaknessesCWE-125

Technical details

References

Community reviews

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