pyjwt — security advisory
PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, is_pem_format in jwt/utils.py is affected because is_pem_format does not recognize every PEM representation accepted by the cryptography loader. This occurs when an application mixes HMAC and asymmetric algorithms and supplies a mutated public-key PEM as raw key bytes. As a result, HMACAlgorithm.prepare_key treats the unrecognized asymmetric public key as an HMAC secret. Consequently, an attacker who knows the public key can forge authenticated HMAC tokens. This issue is fixed in version 2.14.0.
- 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
- 2.14.0-1
- CVEs
- CVE-2026-102268
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 28 Oct 2026, 09:03 UTC · Revision 1
Source evidence
PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, is_pem_format in jwt/utils.py is affected because is_pem_format does not recognize every PEM representation accepted by the cryptography loader. This occurs when an application mixes HMAC and asymmetric algorithms and supplies a mutated public-key PEM as raw key bytes. As a result, HMACAlgorithm.prepare_key treats the unrecognized asymmetric public key as an HMAC secret. Consequently, an attacker who knows the public key can forge authenticated HMAC tokens. This issue is fixed in version 2.14.0.
osv:DEBIAN-CVE-2026-102268
pyjwt
Fixed versions: Not specified
pyjwt
Fixed versions: Not specified
pyjwt
Fixed versions: 2.14.0-1
Complete source record
{
"id": "230cb5ee1de9db7f517759132e2a97458a2dbe838ac4af43ee95d4e1bd9dda89",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-102268",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-102268",
"summary": "PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, is_pem_format in jwt/utils.py is affected because is_pem_format does not recognize every PEM representation accepted by the cryptography loader. This occurs when an application mixes HMAC and asymmetric algorithms and supplies a mutated public-key PEM as raw key bytes. As a result, HMACAlgorithm.prepare_key treats the unrecognized asymmetric public key as an HMAC secret. Consequently, an attacker who knows the public key can forge authenticated HMAC tokens. This issue is fixed in version 2.14.0.",
"evidence": "osv:DEBIAN-CVE-2026-102268",
"products": [
{
"name": {
"value": "pyjwt",
"evidence": "/affected/0/package/name"
},
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"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"
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{
"value": "2.10.1-4",
"evidence": "/affected/0/versions"
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{
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{
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"evidence": "/affected/0/versions"
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{
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{
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{
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{
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{
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{
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{
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{
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{
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"evidence": "/affected/1/versions"
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{
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{
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"evidence": "/affected/1/versions"
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{
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{
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{
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{
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"evidence": "/affected/2/versions"
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{
"value": "2.10.1-3",
"evidence": "/affected/2/versions"
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{
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{
"value": "2.11.0-2",
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{
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{
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],
"severity": "critical",
"structured": {
"id": "DEBIAN-CVE-2026-102268",
"aliases": [
"DEBIAN-CVE-2026-102268"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"
}
],
"affected": [
{
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"package": {
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"purl": "pkg:deb/debian/pyjwt?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
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"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-102268.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
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},
{
"ranges": [
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"package": {
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"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-2026-102268.json"
},
"ecosystem_specific": {
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}
},
{
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{
"type": "ECOSYSTEM",
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{
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},
{
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],
"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",
"2.13.0-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-102268.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-08T09:47:39.536137543Z",
"provider": "osv",
"upstream": [
"CVE-2026-102268"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-102268"
]
},
"related_cves": [
{
"value": "CVE-2026-102268",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 98920,
"published_at": "2026-09-28T21:17:14.6+00:00"
}