CVE-2024-9143: Issue summary: Use of the low-level GF(2^m) elliptic curve APIs with untrusted explicit values for the field polynomial can lead to out-of-bounds memory reads o

Issue summary: Use of the low-level GF(2^m) elliptic curve APIs with untrusted explicit values for the field polynomial can lead to out-of-bounds memory reads o

Issue summary: Use of the low-level GF(2^m) elliptic curve APIs with untrusted explicit values for the field polynomial can lead to out-of-bounds memory reads or writes. Impact summary: Out of bound memory writes can lead to an application crash or even a possibility of a remote code execution, however, in all the protocols involving Elliptic Curve Cryptography that we're aware of, either only "named curves" are supported, or, if explicit curve parameters are supported, they specify an X9.62 encoding of binary (GF(2^m)) curves that can't represent problematic input values. Thus the likelihood of existence of a vulnerable application is low. In particular, the X9.62 encoding is used for ECC keys in X.509 certificates, so problematic inputs cannot occur in the context of processing X.509 certificates. Any problematic use-cases would have to be using an "exotic" curve encoding. The affected APIs include: EC_GROUP_new_curve_GF2m(), EC_GROUP_new_from_params(), and various supporting BN_GF2m_*() functions. Applications working with "exotic" explicit binary (GF(2^m)) curve parameters, that make it possible to represent invalid field polynomials with a zero constant term, via the abov

Description from the National Vulnerability Database, published by openssl-security@openssl.org

What it means for a small business

OpenSSL runs on web servers, so this is mostly your hosting company's to fix. On shared hosting you can't patch it yourself, but you can ask.

Ask your host whether your server runs it, whether it's updated, and on what date. A good host answers that in a day.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 5.8%, top 7% of all CVEs. That’s above average: worth scheduling this week. Scored October 28, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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