VulnerabilityPublished 22 Aug 2024Updated 10 Sep 2024

CVE-2024-45193: olm · Weak Cryptography

Affects olmSource CVE Database V5

Not known to be exploited · CVSS 4.3 Medium · end of life, no fix coming : replace or isolate olm; no fix will be released.

Data as of 26 Oct 2026, 15:59 UTC

CVSS 3.1 base score

4.3Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 22% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: None coming – the product is end of life

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: Low
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: 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: 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: None: There is no loss of confidentiality within 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: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 22 Aug 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

No fix will be released: olm is end of life. Replace it, or isolate it from untrusted networks until you can.

Affected software

Product	Affected	Fixed in
GitHubmatrix-org/olm`pkg:github/matrix-org/olm`Other threats	Affected <=3.2.16	Fixed in–

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

AI-suggested

Given that the vulnerability affects only unsupported products using libolm and no patches are available, mitigation strategies should focus on migration and risk reduction. Organizations should: 1) Identify and inventory all systems using Matrix libolm versions up to 3.2.16 or unsupported forks. 2) Upgrade to supported Matrix implementations or cryptographic libraries that have addressed Ed25519 signature validation properly, ensuring S < n checks are enforced. 3) If upgrading is not immediately possible, isolate vulnerable systems from untrusted networks to reduce exploitation risk. 4) Employ additional cryptographic verification layers or application-level signature checks where feasible to detect malleable signatures. 5) Monitor network traffic and logs for anomalous signature patterns or replay attempts. 6) Engage with Matrix community or maintainers for guidance on secure alternatives or patches. 7) Plan deprecation of legacy Matrix deployments relying on vulnerable libolm versions. These steps go beyond generic advice by emphasizing inventory, isolation, layered verification, and community engagement.

Description

An issue was discovered in Matrix libolm through 3.2.16. There is Ed25519 signature malleability due to lack of validation criteria (does not ensure that S < n). This refers to the libolm implementation of Olm. NOTE: This vulnerability only affects products that are no longer supported by the maintainer.

Impact

The primary impact of CVE-2024-45193 is on the integrity of cryptographic signatures within affected Matrix libolm implementations. Signature malleability can allow attackers to forge alternate valid signatures for the same message, potentially enabling replay attacks, signature substitution, or undermining non-repudiation guarantees. This could lead to unauthorized message acceptance or verification failures in secure messaging contexts. However, confidentiality and availability remain unaffected. The vulnerability requires network access and low privileges but no user interaction, which moderately increases the risk of exploitation in exposed environments. Since the affected products are no longer supported, organizations continuing to use legacy Matrix implementations may face increased risk due to lack of patches and mitigations. This could impact secure communications, especially in environments relying on Matrix for end-to-end encrypted messaging. The absence of known exploits reduces immediate risk but does not eliminate potential future exploitation. Overall, the impact is moderate but significant for organizations dependent on the integrity of Matrix cryptographic operations in unsupported versions.

CWE-327Use of a Broken or Risky Cryptographic Algorithm (opens in a new tab)
Class weaknessLikelihood of exploit: HighOWASP Top 10 A04:2025: Cryptographic Failures (opens in a new tab)
The product uses a broken or risky cryptographic algorithm or protocol.
Architecture and Design · Libraries or Frameworks
When there is a need to store or transmit sensitive data, use strong, up-to-date cryptographic algorithms to encrypt that data. Select a well-vetted algorithm that is currently considered to be strong by experts in the field, and use well-tested implementations.
Architecture and Design
Ensure that the design allows one cryptographic algorithm to be replaced with another in the next generation or version. Where possible, use wrappers to make the interfaces uniform. This will make it easier to upgrade to stronger algorithms.
Architecture and Design
Carefully manage and protect cryptographic keys (see CWE-320). If the keys can be guessed or stolen, then the strength of the cryptography itself is irrelevant.
OWASP Cheat Sheets
Cryptographic Storage (opens in a new tab)
Key Management (opens in a new tab)
Transport Layer Protection (opens in a new tab)
User Privacy Protection (opens in a new tab)
Password Storage (opens in a new tab)
OWASP ASVS 4.0.3
V8.3.7 (opens in a new tab)
V2.9.3 (opens in a new tab)
V6.2.2 (opens in a new tab)
Attack patterns
Encryption Brute Forcing (opens in a new tab)
Creating a Rogue Certification Authority Certificate (opens in a new tab)
Signature Spoof (opens in a new tab)
Signature Spoofing by Improper Validation (opens in a new tab)
Cryptanalysis of Cellular Encryption (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 28 Feb 2026, 06:55 UTC

WeaknessesCWE-327

Technical details

References

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