How severe is CVE-2026-74876?

CVE-2026-74876 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-74876 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-74876?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2026-74876 published?

CVE-2026-74876 was published on 2026-08-17.

CVE-2026-74876

CVE-2026-74876 is a critical-severity vulnerability with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-347.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 9.3
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Published: 2026-08-17
Last modified: 2026-08-17

Description

openssl_encrypt versions before 1.4.0 contain a vulnerability in PublicKeyBundle.from_dict() that creates key bundles from untrusted data without verifying signatures. Attackers can call from_dict() followed by to_identity() without signature verification to encrypt data using attacker-controlled public keys, leaking secrets.

Frequently asked questions

What is CVE-2026-74876?: openssl_encrypt versions before 1.4.0 contain a vulnerability in PublicKeyBundle.from_dict() that creates key bundles from untrusted data without verifying signatures. Attackers can call from_dict() followed by to_identity() without signature verification to encrypt data using attacker-controlled public keys, leaking secrets.
How severe is CVE-2026-74876?: CVE-2026-74876 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-74876 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-74876?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2026-74876 published?: CVE-2026-74876 was published on 2026-08-17.

References

Other CWE-347 (Improper Verification of Cryptographic Signature) vulnerabilities

CVE-2026-5430 — Critical (CVSS 10.0): The JWT authentication mechanism accepts tokens signed with algorithms other than those explicitly configured or…
CVE-2026-56451 — Critical (CVSS 10.0): A vulnerability has been identified in Opcenter X (All versions < V2604). Affected applications do not properly…
CVE-2026-48558 — Critical (CVSS 10.0): SimpleHelp versions 5.5.15 and prior and 6.0 pre-release versions contain an authentication bypass vulnerability in the…
CVE-2023-25574 — Critical (CVSS 10.0): `jupyterhub-ltiauthenticator` is a JupyterHub authenticator for learning tools interoperability (LTI).…
CVE-2024-45409 — Critical (CVSS 10.0): The Ruby SAML library is for implementing the client side of a SAML authorization. Ruby-SAML in <= 12.2 and 1.13.0 <=…
CVE-2024-32962 — Critical (CVSS 10.0): xml-crypto is an xml digital signature and encryption library for Node.js. In affected versions the default…

Browse all CWE-347 (Improper Verification of Cryptographic Signature) vulnerabilities →