LowFix available
pyjwt — security advisory
PyJWT is a JSON Web Token implementation in Python. Prior to 2.13.0, PyJWKClient.get_signing_key() forces a fresh HTTP request to the JWKS endpoint for every JWT with an unknown kid value, with no rate limiting. Since kid comes from the unverified token header, an attacker can trigger unlimited outbound requests. The vulnerability surfaces only when a JWKS fetch fails; an attacker can attempt to provoke that with sustained unknown-kid traffic, but the outcome depends on upstream JWKS-endpoint behavior (rate limiting, transient errors) which is beyond the attacker's control. This vulnerability is fixed in 2.13.0.
- Products
- pyjwt
- Affected versions
- 2.10.1-1, 2.10.1-2, 2.10.1-2+deb13u1, 2.10.1-3, 2.10.1-4, 2.11.0-2, 2.12.1-1, 2.13.0-1, 2.14.0-1, 2.15.0-1, 2.15.1-1, 2.6.0-1, 2.6.0-1+deb12u1, 2.7.0-1
- Fixed versions
- 2.13.0-1
- CVEs
- CVE-2026-48524
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 17:48 UTC · Revision 2
Source evidence
PyJWT is a JSON Web Token implementation in Python. Prior to 2.13.0, PyJWKClient.get_signing_key() forces a fresh HTTP request to the JWKS endpoint for every JWT with an unknown kid value, with no rate limiting. Since kid comes from the unverified token header, an attacker can trigger unlimited outbound requests. The vulnerability surfaces only when a JWKS fetch fails; an attacker can attempt to provoke that with sustained unknown-kid traffic, but the outcome depends on upstream JWKS-endpoint behavior (rate limiting, transient errors) which is beyond the attacker's control. This vulnerability is fixed in 2.13.0.
osv:DEBIAN-CVE-2026-48524
pyjwt
Fixed versions: Not specified
pyjwt
Fixed versions: Not specified
pyjwt
Fixed versions: 2.13.0-1
Complete source record
{
"id": "65b3c14d3aad9d30f1fc4ba7599a715cf7876900b26edd72de23093bf2049215",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-48524",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-48524",
"summary": "PyJWT is a JSON Web Token implementation in Python. Prior to 2.13.0, PyJWKClient.get_signing_key() forces a fresh HTTP request to the JWKS endpoint for every JWT with an unknown kid value, with no rate limiting. Since kid comes from the unverified token header, an attacker can trigger unlimited outbound requests. The vulnerability surfaces only when a JWKS fetch fails; an attacker can attempt to provoke that with sustained unknown-kid traffic, but the outcome depends on upstream JWKS-endpoint behavior (rate limiting, transient errors) which is beyond the attacker's control. This vulnerability is fixed in 2.13.0.",
"evidence": "osv:DEBIAN-CVE-2026-48524",
"products": [
{
"name": {
"value": "pyjwt",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.10.1-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.10.1-2",
"evidence": "/affected/0/versions"
},
{
"value": "2.10.1-3",
"evidence": "/affected/0/versions"
},
{
"value": "2.10.1-4",
"evidence": "/affected/0/versions"
},
{
"value": "2.11.0-2",
"evidence": "/affected/0/versions"
},
{
"value": "2.12.1-1",
"evidence": "/affected/0/versions"
},
{
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"evidence": "/affected/0/versions"
},
{
"value": "2.14.0-1",
"evidence": "/affected/0/versions"
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{
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"evidence": "/affected/0/versions"
},
{
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"evidence": "/affected/0/versions"
},
{
"value": "2.6.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "2.6.0-1+deb12u1",
"evidence": "/affected/0/versions"
},
{
"value": "2.7.0-1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
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"evidence": "/affected/1/package/name"
},
"prerequisites": [],
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"affected_versions": [
{
"value": "2.10.1-2",
"evidence": "/affected/1/versions"
},
{
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"evidence": "/affected/1/versions"
},
{
"value": "2.10.1-3",
"evidence": "/affected/1/versions"
},
{
"value": "2.10.1-4",
"evidence": "/affected/1/versions"
},
{
"value": "2.11.0-2",
"evidence": "/affected/1/versions"
},
{
"value": "2.12.1-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.13.0-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.14.0-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.15.0-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.15.1-1",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
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"evidence": "/affected/2/package/name"
},
"prerequisites": [],
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"evidence": "/affected/2/ranges"
}
],
"affected_versions": [
{
"value": "2.10.1-2",
"evidence": "/affected/2/versions"
},
{
"value": "2.10.1-3",
"evidence": "/affected/2/versions"
},
{
"value": "2.10.1-4",
"evidence": "/affected/2/versions"
},
{
"value": "2.11.0-2",
"evidence": "/affected/2/versions"
},
{
"value": "2.12.1-1",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "low",
"structured": {
"id": "DEBIAN-CVE-2026-48524",
"aliases": [
"DEBIAN-CVE-2026-48524"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
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],
"package": {
"name": "pyjwt",
"purl": "pkg:deb/debian/pyjwt?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
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"2.10.1-3",
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"2.14.0-1",
"2.15.0-1",
"2.15.1-1",
"2.6.0-1",
"2.6.0-1+deb12u1",
"2.7.0-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48524.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
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}
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}
],
"package": {
"name": "pyjwt",
"purl": "pkg:deb/debian/pyjwt?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"2.10.1-2",
"2.10.1-2+deb13u1",
"2.10.1-3",
"2.10.1-4",
"2.11.0-2",
"2.12.1-1",
"2.13.0-1",
"2.14.0-1",
"2.15.0-1",
"2.15.1-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48524.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.13.0-1"
}
]
}
],
"package": {
"name": "pyjwt",
"purl": "pkg:deb/debian/pyjwt?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"2.10.1-2",
"2.10.1-3",
"2.10.1-4",
"2.11.0-2",
"2.12.1-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48524.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-27T09:47:37.526376854Z",
"provider": "osv",
"upstream": [
"CVE-2026-48524"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-48524"
]
},
"related_cves": [
{
"value": "CVE-2026-48524",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 461233,
"published_at": "2026-05-28T16:16:29.403+00:00"
}