--- id: CVE-2026-31790 title: |- Issue summary: Applications using RSASVE key encapsulation to establish a secret encryption key can send contents of an uninitialized memory buffer to a malicious peer. Impact summary: The uninitialized buffer might contain sensitive da… summary: |- Issue summary: Applications using RSASVE key encapsulation to establish a secret encryption key can send contents of an uninitialized memory buffer to a malicious peer. Impact summary: The uninitialized buffer might contain sensitive da… severity: high cvss: 7.5 cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N' cwe: - CWE-754 - CWE-824 vendor: openssl product: openssl affected: - 'openssl >= 3.0.0, < 3.0.20' - 'openssl >= 3.3.0, < 3.3.7' - 'openssl >= 3.4.0, < 3.4.5' - 'openssl >= 3.5.0, < 3.5.6' - 'openssl >= 3.6.0, < 3.6.2' patched: - openssl 3.6.2 published: '2026-04-07' updated: '2026-07-24' source: NVD sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-31790' references: - url: >- https://github.com/openssl/openssl/commit/001e01db3e996e13ffc72386fe79d03a6683b5ac label: openssl-security@openssl.org - url: >- https://github.com/openssl/openssl/commit/abd8b2eec7e3f3fda60ecfb68498b246b52af482 label: openssl-security@openssl.org - url: >- https://github.com/openssl/openssl/commit/b922e24e5b23ffb9cb9e14cadff23d91e9f7e406 label: openssl-security@openssl.org - url: >- https://github.com/openssl/openssl/commit/d5f8e71cd0a54e961d0c3b174348f8308486f790 label: openssl-security@openssl.org - url: >- https://github.com/openssl/openssl/commit/eed200f58cd8645ed77e46b7e9f764e284df379e label: openssl-security@openssl.org - url: 'https://openssl-library.org/news/secadv/20260407.txt' label: openssl-security@openssl.org - url: 'https://cert-portal.siemens.com/productcert/html/ssa-032379.html' label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e - url: >- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31790.json - url: 'https://access.redhat.com/security/cve/CVE-2026-31790' - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2451094' - url: 'https://www.cve.org/CVERecord?id=CVE-2026-31790' - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-31790' - url: 'https://access.redhat.com/errata/RHSA-2026:54187' - url: 'https://access.redhat.com/errata/RHSA-2026:43252' - url: 'https://access.redhat.com/errata/RHSA-2026:43226' - url: 'https://access.redhat.com/errata/RHSA-2026:44231' - url: 'https://access.redhat.com/errata/RHSA-2026:39297' - url: 'https://access.redhat.com/errata/RHSA-2026:19066' - url: 'https://access.redhat.com/errata/RHSA-2026:19218' - url: 'https://access.redhat.com/errata/RHSA-2026:27745' - url: 'https://access.redhat.com/errata/RHSA-2026:27746' - url: 'https://access.redhat.com/errata/RHSA-2026:28832' - url: 'https://access.redhat.com/errata/RHSA-2026:27744' - url: 'https://access.redhat.com/errata/RHSA-2026:39981' - url: 'https://access.redhat.com/errata/RHSA-2026:27998' - url: 'https://access.redhat.com/errata/RHSA-2026:33313' - url: 'https://access.redhat.com/errata/RHSA-2026:28211' - url: 'https://access.redhat.com/errata/RHSA-2026:7261' - url: 'https://access.redhat.com/errata/RHSA-2026:22634' - url: 'https://access.redhat.com/errata/RHSA-2026:34102' - url: 'https://access.redhat.com/errata/RHSA-2026:12195' - url: 'https://access.redhat.com/errata/RHSA-2026:44481' - url: 'https://access.redhat.com/errata/RHSA-2026:58981' - url: 'https://access.redhat.com/errata/RHSA-2026:21275' - url: 'https://access.redhat.com/errata/RHSA-2026:71542' tags: - nvd - csaf - vex - red-hat epss: 0.00448 epssPercentile: 0.36233 ingestedAt: '2026-07-25T23:05:58.234Z' scores: nvd: 7.5 vendor: 5.9 --- ## Overview Issue summary: Applications using RSASVE key encapsulation to establish a secret encryption key can send contents of an uninitialized memory buffer to a malicious peer. Impact summary: The uninitialized buffer might contain sensitive data from the previous execution of the application process which leads to sensitive data leakage to an attacker. RSA_public_encrypt() returns the number of bytes written on success and -1 on error. The affected code tests only whether the return value is non-zero. As a result, if RSA encryption fails, encapsulation can still return success to the caller, set the output lengths, and leave the caller to use the contents of the ciphertext buffer as if a valid KEM ciphertext had been produced. If applications use EVP_PKEY_encapsulate() with RSA/RSASVE on an attacker-supplied invalid RSA public key without first validating that key, then this may cause stale or uninitialized contents of the caller-provided ciphertext buffer to be disclosed to the attacker in place of the KEM ciphertext. As a workaround calling EVP_PKEY_public_check() or EVP_PKEY_public_check_quick() before EVP_PKEY_encapsulate() will mitigate the issue. The FIPS modules in 3.6, 3.5, 3.4, 3.3, 3.1 and 3.0 are affected by this issue. ## Affected - `openssl >= 3.0.0, < 3.0.20` - `openssl >= 3.3.0, < 3.3.7` - `openssl >= 3.4.0, < 3.4.5` - `openssl >= 3.5.0, < 3.5.6` - `openssl >= 3.6.0, < 3.6.2` ## Remediation Upgrade past the affected range: - `openssl 3.6.2` ## Vendor advisories - **RHSA-2026:54187** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.13 · released 2026-08-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:54187) - **RHSA-2026:43252** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.14 · released 2026-07-31 · [advisory](https://access.redhat.com/errata/RHSA-2026:43252) - **RHSA-2026:43226** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.15 · released 2026-07-31 · [advisory](https://access.redhat.com/errata/RHSA-2026:43226) - **RHSA-2026:44231** · Red Hat · fixed in: Red Hat OpenShift Container Platform 4.19 · released 2026-07-29 · [advisory](https://access.redhat.com/errata/RHSA-2026:44231) - **RHSA-2026:39297** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) · released 2026-07-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:39297) - **RHSA-2026:19066** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10) · released 2026-05-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:19066) - **RHSA-2026:19218** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9) · released 2026-05-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:19218) - **RHSA-2026:27745** · Red Hat · fixed in: Red Hat Enterprise Linux BaseOS EUS (v. 10.0) · released 2026-06-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:27745) - **RHSA-2026:27746** · Red Hat · fixed in: Red Hat Enterprise Linux BaseOS (v. 10) · released 2026-06-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:27746) - **RHSA-2026:28832** · Red Hat · fixed in: Red Hat Enterprise Linux BaseOS E4S (v.9.2), Red Hat Enterprise Linux BaseOS E4S (v.9.4), Red Hat Enterprise Linux BaseOS EUS (v.9.6) · released 2026-06-24 · [advisory](https://access.redhat.com/errata/RHSA-2026:28832) - **RHSA-2026:27744** · Red Hat · fixed in: Red Hat Enterprise Linux BaseOS (v. 9) · released 2026-06-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:27744) - **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat OpenShift Container Platform 4, Red Hat Enterprise Linux 9 · updated 2026-09-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31790.json) - **RHSA-2026:71542** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux BaseOS EUS (v. 10.0) · released 2026-09-24 · [advisory](https://access.redhat.com/errata/RHSA-2026:71542)