How severe is CVE-2026-48526?

CVE-2026-48526 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-48526 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-48526?

CVE-2026-48526 affects Pyjwt Project Pyjwt. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-48526?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-48526 have an EU (EUVD) identifier?

Yes. CVE-2026-48526 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32917.

When was CVE-2026-48526 published?

CVE-2026-48526 was published on 2026-05-28 and last updated on 2026-08-17.

CVE-2026-48526

CVE-2026-48526 is a high-severity vulnerability in Pyjwt Project Pyjwt with a CVSS 3.x base score of 7.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: High (CVSS 3.x base score 7.4)
EPSS exploit prediction: 0% (33rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-32917
Weakness: CWE-287
Affected product: Pyjwt Project Pyjwt
Published: 2026-05-28
Last modified: 2026-08-17

Description

PyJWT is a JSON Web Token implementation in Python. Prior to 2.13.0, when the verifier is decoding JSON Web Tokens, while supporting both asymmetric and HMAC algorithms, the library does not validate use of JSON Web Keys in HMAC algorithm, allowing attacker to use the issuer public key as the secret key for HMAC algorithm. This vulnerability is fixed in 2.13.0.

Frequently asked questions

What is CVE-2026-48526?: PyJWT is a JSON Web Token implementation in Python. Prior to 2.13.0, when the verifier is decoding JSON Web Tokens, while supporting both asymmetric and HMAC algorithms, the library does not validate use of JSON Web Keys in HMAC algorithm, allowing attacker to use the issuer public key as the secret key for HMAC algorithm. This vulnerability is fixed in 2.13.0.
How severe is CVE-2026-48526?: CVE-2026-48526 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-48526 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-48526?: CVE-2026-48526 affects Pyjwt Project Pyjwt. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-48526?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-48526 have an EU (EUVD) identifier?: Yes. CVE-2026-48526 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32917.
When was CVE-2026-48526 published?: CVE-2026-48526 was published on 2026-05-28 and last updated on 2026-08-17.

References

Affected products (1)

cpe:2.3:a:pyjwt_project:pyjwt:*:*:*:*:*:*:*:*

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