CVE-2026-85394
published 2026-09-03CVE-2026-85394: python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH…
PriorityP348critical9.1CVSS 3.1
AVNACLPRNUINSUCHIHAN
EPSS
0.22%
12.2th percentile
python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| python-jose_project | python-jose | 0 – 3.5.0 | — |
| rhoai | odh-llama-stack-core-rhel9 | — | — |
CVSS provenance
nvdv3.19.1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
nvdv4.09.3CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
ghsa6.5MEDIUM
vendor_redhat6.5MEDIUM
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VulDB
mpdavis python-jose up to 3.5.0 HMAC initialization input validation (EUVD-2026-70671)
vuldb·2026-09-03·CVSS 9.1
CVE-2026-85394 [CRITICAL] mpdavis python-jose up to 3.5.0 HMAC initialization input validation (EUVD-2026-70671)
A vulnerability, which was classified as critical, has been found in mpdavis python-jose up to 3.5.0. This issue affects the function HMAC initialization. The manipulation leads to improper input validation.
This vulnerability is uniquely identified as CVE-2026-85394. The attack is possible to be carried out remotely. No exploit exists.
GHSA
python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes.
ghsa_unreviewed·2026-09-03·CVSS 6.5
CVE-2026-85394 [MEDIUM] CWE-347 python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes.
python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.
GHSA
python-jose algorithm confusion guard bypassed by DER-encoded public keys
ghsa·2026-09-03·CVSS 6.5
CVE-2026-85394 [MEDIUM] CWE-347 python-jose algorithm confusion guard bypassed by DER-encoded public keys
python-jose algorithm confusion guard bypassed by DER-encoded public keys
python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.
Red Hat
jose: python-jose: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret
vendor_redhat·2026-09-03·CVSS 6.5
CVE-2026-85394 [MEDIUM] CWE-347 jose: python-jose: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret
jose: python-jose: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret
python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.
A flaw was found in python-jose. A remote attacker who obtains the service's public key can exploit an algorithm confusion vulnerability when signature verification algorithms are not strictly restricted. By utilizing a specifically formatted public key as a shared secret key, the attacker can forge valid JSON Web Tokens (JWTs). This flaw allo
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-85394 python-josepy: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [epel-all]
bugzilla·2026-10-05·CVSS 6.5
CVE-2026-85394 [MEDIUM] CVE-2026-85394 python-josepy: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [epel-all]
CVE-2026-85394 python-josepy: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [epel-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.
Bugzilla
CVE-2026-85394 python-jose: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [epel-all]
bugzilla·2026-10-05·CVSS 6.5
CVE-2026-85394 [MEDIUM] CVE-2026-85394 python-jose: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [epel-all]
CVE-2026-85394 python-jose: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [epel-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.
Bugzilla
CVE-2026-85394 python-joserfc: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [fedora-all]
bugzilla·2026-10-05·CVSS 6.5
CVE-2026-85394 [MEDIUM] CVE-2026-85394 python-joserfc: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [fedora-all]
CVE-2026-85394 python-joserfc: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.
Bugzilla
CVE-2026-85394 python-josepy: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [fedora-all]
bugzilla·2026-10-05·CVSS 6.5
CVE-2026-85394 [MEDIUM] CVE-2026-85394 python-josepy: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [fedora-all]
CVE-2026-85394 python-josepy: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.
Bugzilla
CVE-2026-85394 jose: python-jose: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret
bugzilla·2026-09-03·CVSS 6.5
CVE-2026-85394 [MEDIUM] CVE-2026-85394 jose: python-jose: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret
CVE-2026-85394 jose: python-jose: python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret
python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.
https://github.com/advisories/GHSA-6c5p-j8vq-pqhjhttps://github.com/mpdavis/python-josehttps://github.com/mpdavis/python-jose/blob/018b310ddb8b50dcfd09a0c152117835a21dd656/jose/backends/native.pyhttps://github.com/mpdavis/python-jose/blob/018b310ddb8b50dcfd09a0c152117835a21dd656/jose/utils.pyhttps://github.com/mpdavis/python-jose/issues/414https://www.vulncheck.com/advisories/python-jose-through-3.5.0-algorithm-confusion-via-der-encoded-public-key-as-hmac-secret
2026-09-03
Published