OESA-2026-1923 (CVE-2026-39373)
Vulnerability from osv_openeuler – Published: 2026-04-17 11:10 – Updated: 2026-08-06 11:10 – Source websiteImplements JWK, JWS, JWE specifications with python-cryptography
Security Fix(es):
JWCrypto implements JWK, JWS, and JWE specifications using python-cryptography. Prior to 1.5.7, an unauthenticated attacker can exhaust server memory by sending crafted JWE tokens with ZIP compression. The existing patch for CVE-2024-28102 limits input token size to 250KB but does not validate the decompressed output size. An unauthenticated attacker can cause memory exhaustion on memory-constrained systems. A token under the 250KB input limit can decompress to approximately 100MB. This vulnerability is fixed in 1.5.7.(CVE-2026-39373)
| URL | Type | |
|---|---|---|
{
"affected": [
{
"ecosystem_specific": {
"noarch": [
"python-jwcrypto-help-1.5.0-4.oe2403sp2.noarch.rpm",
"python3-jwcrypto-1.5.0-4.oe2403sp2.noarch.rpm"
],
"src": [
"python-jwcrypto-1.5.0-4.oe2403sp2.src.rpm"
]
},
"package": {
"ecosystem": "openEuler:24.03-LTS-SP2",
"name": "python-jwcrypto",
"purl": "pkg:rpm/openEuler/python-jwcrypto\u0026distro=openEuler-24.03-LTS-SP2"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.5.0-4.oe2403sp2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"severity": "Medium"
},
"details": "Implements JWK, JWS, JWE specifications with python-cryptography\r\n\r\nSecurity Fix(es):\n\nJWCrypto implements JWK, JWS, and JWE specifications using python-cryptography. Prior to 1.5.7, an unauthenticated attacker can exhaust server memory by sending crafted JWE tokens with ZIP compression. The existing patch for CVE-2024-28102 limits input token size to 250KB but does not validate the decompressed output size. An unauthenticated attacker can cause memory exhaustion on memory-constrained systems. A token under the 250KB input limit can decompress to approximately 100MB. This vulnerability is fixed in 1.5.7.(CVE-2026-39373)",
"id": "OESA-2026-1923",
"modified": "2026-08-06T11:10:56Z",
"published": "2026-04-17T11:10:56Z",
"references": [
{
"type": "ADVISORY",
"url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1923"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39373"
}
],
"schema_version": "1.7.2",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
"type": "CVSS_V3"
}
],
"summary": "python-jwcrypto security update",
"upstream": [
"CVE-2026-39373"
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
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