OESA-2026-2602 (CVE-2026-31790)
Vulnerability from osv_openeuler – Published: 2026-06-05 11:11 – Updated: 2026-08-06 11:11 – Source websiteEDK II is a modern, feature-rich, cross-platform firmware development environment for the UEFI and PI specifications.
Security Fix(es):
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.(CVE-2026-31790)
| URL | Type | |
|---|---|---|
{
"affected": [
{
"ecosystem_specific": {
"aarch64": [
"edk2-debuginfo-202308-33.oe2403sp1.aarch64.rpm",
"edk2-debugsource-202308-33.oe2403sp1.aarch64.rpm",
"edk2-devel-202308-33.oe2403sp1.aarch64.rpm"
],
"noarch": [
"edk2-aarch64-202308-33.oe2403sp1.noarch.rpm",
"edk2-help-202308-33.oe2403sp1.noarch.rpm",
"edk2-ovmf-202308-33.oe2403sp1.noarch.rpm",
"python3-edk2-devel-202308-33.oe2403sp1.noarch.rpm"
],
"src": [
"edk2-202308-33.oe2403sp1.src.rpm"
],
"x86_64": [
"edk2-debuginfo-202308-33.oe2403sp1.x86_64.rpm",
"edk2-debugsource-202308-33.oe2403sp1.x86_64.rpm",
"edk2-devel-202308-33.oe2403sp1.x86_64.rpm"
]
},
"package": {
"ecosystem": "openEuler:24.03-LTS-SP1",
"name": "edk2",
"purl": "pkg:rpm/openEuler/edk2\u0026distro=openEuler-24.03-LTS-SP1"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "202308-33.oe2403sp1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"severity": "High"
},
"details": "EDK II is a modern, feature-rich, cross-platform firmware development environment for the UEFI and PI specifications.\r\n\r\nSecurity Fix(es):\n\nIssue summary: Applications using RSASVE key encapsulation to establish\na secret encryption key can send contents of an uninitialized memory buffer to\na malicious peer.\n\nImpact summary: The uninitialized buffer might contain sensitive data from the\nprevious execution of the application process which leads to sensitive data\nleakage to an attacker.\n\nRSA_public_encrypt() returns the number of bytes written on success and -1\non error. The affected code tests only whether the return value is non-zero.\nAs a result, if RSA encryption fails, encapsulation can still return success to\nthe caller, set the output lengths, and leave the caller to use the contents of\nthe ciphertext buffer as if a valid KEM ciphertext had been produced.\n\nIf applications use EVP_PKEY_encapsulate() with RSA/RSASVE on an\nattacker-supplied invalid RSA public key without first validating that key,\nthen this may cause stale or uninitialized contents of the caller-provided\nciphertext buffer to be disclosed to the attacker in place of the KEM\nciphertext.\n\nAs a workaround calling EVP_PKEY_public_check() or\nEVP_PKEY_public_check_quick() before EVP_PKEY_encapsulate() will mitigate\nthe issue.\n\nThe FIPS modules in 3.6, 3.5, 3.4, 3.3, 3.1 and 3.0 are affected by this issue.(CVE-2026-31790)",
"id": "OESA-2026-2602",
"modified": "2026-08-06T11:11:32Z",
"published": "2026-06-05T11:11:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-2602"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31790"
}
],
"schema_version": "1.7.2",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "edk2 security update",
"upstream": [
"CVE-2026-31790"
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
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