MediumCVE-2026-65628

    Infinite recursion (CPU denial-of-service) in JOSE.JWK.shared_secret/2 on mismatched key types (CVE-2026-65628)

    Published Last modified Sources: CVE.org, OSV

    What is affected, what to do

    jose_jwk:shared_secret/2 (exposed in Elixir as JOSE.JWK.shared_secret/2) derives an ECDH shared secret from two JWKs. Its first function clause only matches when both JWKs carry the same key type (kty) module, and its fallback clause re-invokes itself as shared_secret(from(YourJWK), from(MyJWK)).

    Update Potatosalad Jose to version 1.11.13.

    Affected
    • Potatosalad Jose lt 1.5.0..1.11.13
    Fixed in
    • Potatosalad Jose 1.11.13

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    5.9

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: Vendor (CNA), CVSS v4

    5.9

    CVSS v4

    Severity Medium on the scale from 0 to 10.

    Source: CVE.org, OSV

    0.1 %

    EPSS score

    Low — model estimates < 1% exploitation likelihood.

    Source: FIRST EPSS, percentile 3.0

    Show all metrics
    Severity
    Medium
    Priority (0–325)

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

    Read in glossary
    59.57 Methodology
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

    Read in glossary
    no public PoC known
    XIEM Effective CVSS

    XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.

    Read in glossary
    5.9 Methodology
    CVSS v4

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    5.9
    EPSS score

    The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.

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    0.1 %
    Low — model estimates < 1% exploitation likelihood.
    EPSS percentile

    The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.

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    3.0
    Low — this CVE sits in the lower 10% of all CVEs scored today.
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    —
    Published
    CWE

    CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.

    Read in glossary
    CWE-674

    Detection rules

    No NEOSEC detection rule is available for this vulnerability yet.

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

    Read in glossary
    Handle the vulnerability in regular vulnerability handling under Art. 21(2)(e) NIS2.
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

    Read in glossary
    From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

    Read in glossary
    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    Description

    jose_jwk:shared_secret/2 (exposed in Elixir as JOSE.JWK.shared_secret/2) derives an ECDH shared secret from two JWKs. Its first function clause only matches when both JWKs carry the same key type (kty) module, and its fallback clause re-invokes itself as shared_secret(from(YourJWK), from(MyJWK)). Because from/1 returns an already-parsed jose_jwk record unchanged, passing two JWKs whose key types differ (for example an EC key and an RSA key) makes the fallback clause re-enter with identical arguments, producing an unbounded tail-recursive loop that never returns and never crashes. An application that derives a shared secret from an externally supplied peer public key without first checking that the peer key's type and curve match its own key can be driven into this loop by an attacker-controlled JWK, pinning an Erlang scheduler at 100% CPU. Repeated requests exhaust the available schedulers, resulting in a denial of service. This issue affects jose: from 1.5.0 before 1.11.13.

    Source: NVD (NIST), cvelistv5, OSV (Open Source Vulnerabilities)

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    Affected versionsFixed in
    potatosaladjose
    • 1.5.0 – < 1.11.13
    • 1.11.13
    hexjose
    • 1.11.0
    • 1.11.6
    • 1.11.4
    • 1.6.1
    • 1.10.0
    • 1.7.6
    • 1.11.8
    • 1.10.1
    • 1.9.0
    • 1.7.9
    • 1.7.8
    • 1.11.10
    • 1.7.0
    • 1.11.1
    • 1.7.2
    • 1.6.0
    • 1.7.5
    • 1.8.4
    • 1.7.3
    • 1.7.4
    • 1.7.1
    • 1.11.9
    • 1.8.2
    • 1.11.2
    • 1.11.11
    • 1.11.5
    • 1.8.1
    • 1.5.2
    • 1.5.0
    • 1.5.1
    • 1.8.3
    • 1.11.7
    • 1.8.0
    • 1.7.7
    • 1.11.12
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    • 1.11.13
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    Vendors and products

    Weakness classes (CWE)

    • CWE-674Uncontrolled Recursion

      Class

      The product does not properly control the amount of recursion that takes place, consuming excessive resources, such as allocated memory or the program stack.

      Entry at MITRE CWE-674

    References & sources

    Changes to this CVE

    Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

    1. ReceivedEEF

      CVSS V4.0: AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

      Weakness type: CWE-674

      Description added or changed

      Show 9 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Descriptionadded
      —
      jose_jwk:shared_secret/2 (exposed in Elixir as JOSE.JWK.shared_secret/2) derives an ECDH shared secret from two JWKs. Its first function clause only matches when both JWKs carry the same key type (kty) module, and its fallback clause re-invokes itself as shared_secret(from(YourJWK), from(MyJWK)). Because from/1 returns an already-parsed jose_jwk record unchanged, passing two JWKs whose key types differ (for example an EC key and an RSA key) makes the fallback clause re-enter with identical arguments, producing an unbounded tail-recursive loop that never returns and never crashes. An application that derives a shared secret from an externally supplied peer public key without first checking that the peer key's type and curve match its own key can be driven into this loop by an attacker-controlled JWK, pinning an Erlang scheduler at 100% CPU. Repeated requests exhaust the available schedulers, resulting in a denial of service. This issue affects jose: from 1.5.0 before 1.11.13.
      CVSSadded
      —
      AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/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
      Weakness type (CWE)added
      —
      CWE-674
      Affected versions (publisher)added
      —
      New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/65xxx/CVE-2026-65628.json">CVE-2026-65628</a>
      Referenceadded
      —
      https://cna.erlef.org/cves/CVE-2026-65628.html
      Referenceadded
      —
      https://github.com/potatosalad/erlang-jose/commit/26182a7de63b91550035d3f08741f7d17f1f675a
      Referenceadded
      —
      https://github.com/potatosalad/erlang-jose/commit/7b80b9f55b9898e1a6901ce136061b241b021d7c
      Referenceadded
      —
      https://github.com/potatosalad/erlang-jose/security/advisories/GHSA-fpj2-9h59-32pp
      Referenceadded
      —
      https://osv.dev/vulnerability/EEF-CVE-2026-65628

      Source identifier: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db

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