VulnerabilityPublished 9 May 2024Updated 19 Aug 2024

CVE-2024-30171: Observable Discrepancy

Source CVE Database V5

Not known to be exploited · CVSS 5.9 Medium · fixed in 1.78 : update affected systems when convenient.

Data as of 26 Oct 2026, 12:29 UTC

CVSS 3.1 base score

5.9Medium

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

EPSS: 0.9% 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 1.78

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

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

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: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
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: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 9 May 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

AI-suggested

To mitigate CVE-2024-30171, organizations should: 1) Upgrade all Bouncy Castle Java TLS API and JSSE Provider instances to version 1.78 or later, where the timing side-channel vulnerability is addressed. 3) Implement network-level protections such as TLS interception detection and anomaly monitoring to identify suspicious timing-based reconnaissance attempts. 4) Where upgrading is not immediately feasible, consider disabling RSA-based handshakes in favor of more secure key exchange methods like ECDHE, which are not affected by this vulnerability. 5) Apply cryptographic best practices including constant-time operations and exception handling to reduce side-channel leakage in custom cryptographic code. 6) Monitor vendor advisories and threat intelligence feeds for any emerging exploit techniques targeting this vulnerability. 7) Perform penetration testing focused on timing side-channels to validate mitigation effectiveness.

Description

An issue was discovered in Bouncy Castle Java TLS API and JSSE Provider before 1.78. Timing-based leakage may occur in RSA based handshakes because of exception processing.

Impact

The primary impact of CVE-2024-30171 is the potential compromise of confidentiality in TLS communications that use RSA handshakes implemented via vulnerable Bouncy Castle libraries. Attackers capable of measuring timing differences during handshake failures may extract sensitive cryptographic information, which could lead to decryption of intercepted TLS traffic or impersonation attacks if private keys are compromised. This undermines the trust model of TLS, affecting secure web services, APIs, and any Java-based applications relying on Bouncy Castle for TLS. While the vulnerability does not affect integrity or availability, the exposure of cryptographic secrets can have severe downstream effects, including data breaches and unauthorized access. Organizations in sectors such as finance, healthcare, government, and critical infrastructure that rely on secure TLS communications are particularly at risk. The lack of known exploits in the wild reduces immediate threat but does not eliminate the risk, especially given the widespread use of Bouncy Castle in enterprise Java environments.

CWE-203Observable Discrepancy (opens in a new tab)
Base weakness
The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.
Architecture and Design · Separation of Privilege
Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
Implementation
Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended).
OWASP Cheat Sheets
Error Handling (opens in a new tab)
Logging (opens in a new tab)
OWASP ASVS 4.0.3
V8.3.4 (opens in a new tab)
V14.3.3 (opens in a new tab)
V7.3.3 (opens in a new tab)
Attack patterns
Black Box Reverse Engineering (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

Description

AI analysisMachine-generated, updated 26 Feb 2026, 17:58 UTC

WeaknessesCWE-203

Technical details

References

Community reviews

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