Summary
PHPECC vulnerable to multiple cryptographic side-channel attacks
ECDSA Canonicalization
PHPECC is vulnerable to malleable ECDSA signature attacks.
Constant-Time Signer
When generating a new ECDSA signature, the GMPMath adapter was used. This class wraps the GNU Multiple Precision arithmetic library (GMP), which does not aim to provide constant-time implementations of algorithms.
An attacker capable of triggering many signatures and studying the time it takes to perform each operation would be able to leak the secret number, k, and thereby learn the private key.
EcDH Timing Leaks
When calculating a shared secret using the EcDH class, the scalar-point multiplication is based on the arithmetic defined by the Point class.
Even though the library implements a Montgomery ladder, the add(), mul(), and getDouble() methods on the Point class are not constant-time. This means that your ECDH private keys are leaking information about each bit of your private key through a timing side-channel.
Impact
GHSA-346H-749J-R28W has a CVSS score of 9.1 (Critical). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. No fixed version is listed yet, so configuration controls and monitoring matter more in the interim.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is GHSA-346H-749J-R28W? GHSA-346H-749J-R28W is a critical-severity security vulnerability in mdanter/ecc (composer), affecting versions >= 0, <= 1.0.0. No fixed version is listed yet.
- How severe is GHSA-346H-749J-R28W? GHSA-346H-749J-R28W has a CVSS score of 9.1 (Critical). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of mdanter/ecc are affected by GHSA-346H-749J-R28W? mdanter/ecc (composer) versions >= 0, <= 1.0.0 is affected.
- Is there a fix for GHSA-346H-749J-R28W? No fixed version is listed for GHSA-346H-749J-R28W yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is GHSA-346H-749J-R28W exploitable, and should I be worried? Whether GHSA-346H-749J-R28W is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-346H-749J-R28W is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.