SUSE-SU-2026:22138-1

Vulnerability from csaf_suse - Published: 2026-06-16 09:09 - Updated: 2026-06-16 09:09
Summary
Security update for python-PyJWT
Severity
Important
Notes
Title of the patch: Security update for python-PyJWT
Description of the patch: This update for python-PyJWT fixes the following issues - CVE-2026-48522: `PyJWKClient` passes URI arguments directly to `urllib.request.urlopen()` and allows for SSRF and token forgery (bsc#1266798). - CVE-2026-48523: verifier-side algorithm allow-list bypass when `jwt.decode()` or `jwt.decode_complete()` are called with a PyJWK key (bsc#1266799). - CVE-2026-48524: unlimited processing of JWTs with unknown kid values by `PyJWKClient.get_signing_key()` leads to unbounded JWKS endpoint requests and DoS (bsc#1266800). - CVE-2026-48525: unbounded Base64URL decoding of unused payload segment in `b64=false` detached JWS allows for DoS (bsc#1266801). - CVE-2026-48526: no validation of use of JSON Web Keys in HMAC algorithm when decoding JSON Web Tokens allows for forged HS256 tokens (bsc#1266802).
Patchnames: SUSE-SLE-Micro-6.1-580
Terms of use: CSAF 2.0 data is provided by SUSE under the Creative Commons License 4.0 with Attribution (CC-BY-4.0).
CVE-2026-48522
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
Affected products
Product Identifier Version Remediation
Unresolved product id: SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch —
Vendor Fix
Threats
Impact moderate
CVE-2026-48523
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Affected products
Product Identifier Version Remediation
Unresolved product id: SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch —
Vendor Fix
Threats
Impact moderate
CVE-2026-48524
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Affected products
Product Identifier Version Remediation
Unresolved product id: SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch —
Vendor Fix
Threats
Impact low
CVE-2026-48525
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
Product Identifier Version Remediation
Unresolved product id: SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch —
Vendor Fix
Threats
Impact important
CVE-2026-48526
7.4 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products
Product Identifier Version Remediation
Unresolved product id: SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch —
Vendor Fix
Threats
Impact important
References
To clipboard 

{
  "document": {
    "aggregate_severity": {
      "namespace": "https://www.suse.com/support/security/rating/",
      "text": "important"
    },
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Copyright 2024 SUSE LLC. All rights reserved.",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en",
    "notes": [
      {
        "category": "summary",
        "text": "Security update for python-PyJWT",
        "title": "Title of the patch"
      },
      {
        "category": "description",
        "text": "This update for python-PyJWT fixes the following issues\n\n- CVE-2026-48522: `PyJWKClient` passes URI arguments directly to `urllib.request.urlopen()` and allows for SSRF and\n  token forgery (bsc#1266798).\n- CVE-2026-48523: verifier-side algorithm allow-list bypass when `jwt.decode()` or `jwt.decode_complete()` are called\n  with a PyJWK key (bsc#1266799).\n- CVE-2026-48524: unlimited processing of JWTs with unknown kid values by `PyJWKClient.get_signing_key()` leads to\n  unbounded JWKS endpoint requests and DoS (bsc#1266800).\n- CVE-2026-48525: unbounded Base64URL decoding of unused payload segment in `b64=false` detached JWS allows for DoS\n  (bsc#1266801).\n- CVE-2026-48526: no validation of use of JSON Web Keys in HMAC algorithm when decoding JSON Web Tokens allows for\n  forged HS256 tokens (bsc#1266802).\n",
        "title": "Description of the patch"
      },
      {
        "category": "details",
        "text": "SUSE-SLE-Micro-6.1-580",
        "title": "Patchnames"
      },
      {
        "category": "legal_disclaimer",
        "text": "CSAF 2.0 data is provided by SUSE under the Creative Commons License 4.0 with Attribution (CC-BY-4.0).",
        "title": "Terms of use"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "https://www.suse.com/support/security/contact/",
      "name": "SUSE Product Security Team",
      "namespace": "https://www.suse.com/"
    },
    "references": [
      {
        "category": "external",
        "summary": "SUSE ratings",
        "url": "https://www.suse.com/support/security/rating/"
      },
      {
        "category": "self",
        "summary": "URL of this CSAF notice",
        "url": "https://ftp.suse.com/pub/projects/security/csaf/suse-su-2026_22138-1.json"
      },
      {
        "category": "self",
        "summary": "URL for SUSE-SU-2026:22138-1",
        "url": "https://www.suse.com/support/update/announcement/2026/suse-su-202622138-1/"
      },
      {
        "category": "self",
        "summary": "E-Mail link for SUSE-SU-2026:22138-1",
        "url": "https://lists.suse.com/pipermail/sle-updates/2026-June/047389.html"
      },
      {
        "category": "self",
        "summary": "SUSE Bug 1266798",
        "url": "https://bugzilla.suse.com/1266798"
      },
      {
        "category": "self",
        "summary": "SUSE Bug 1266799",
        "url": "https://bugzilla.suse.com/1266799"
      },
      {
        "category": "self",
        "summary": "SUSE Bug 1266800",
        "url": "https://bugzilla.suse.com/1266800"
      },
      {
        "category": "self",
        "summary": "SUSE Bug 1266801",
        "url": "https://bugzilla.suse.com/1266801"
      },
      {
        "category": "self",
        "summary": "SUSE Bug 1266802",
        "url": "https://bugzilla.suse.com/1266802"
      },
      {
        "category": "self",
        "summary": "SUSE CVE CVE-2026-48522 page",
        "url": "https://www.suse.com/security/cve/CVE-2026-48522/"
      },
      {
        "category": "self",
        "summary": "SUSE CVE CVE-2026-48523 page",
        "url": "https://www.suse.com/security/cve/CVE-2026-48523/"
      },
      {
        "category": "self",
        "summary": "SUSE CVE CVE-2026-48524 page",
        "url": "https://www.suse.com/security/cve/CVE-2026-48524/"
      },
      {
        "category": "self",
        "summary": "SUSE CVE CVE-2026-48525 page",
        "url": "https://www.suse.com/security/cve/CVE-2026-48525/"
      },
      {
        "category": "self",
        "summary": "SUSE CVE CVE-2026-48526 page",
        "url": "https://www.suse.com/security/cve/CVE-2026-48526/"
      }
    ],
    "title": "Security update for python-PyJWT",
    "tracking": {
      "current_release_date": "2026-06-16T09:09:33Z",
      "generator": {
        "date": "2026-06-16T09:09:33Z",
        "engine": {
          "name": "cve-database.git:bin/generate-csaf.pl",
          "version": "1"
        }
      },
      "id": "SUSE-SU-2026:22138-1",
      "initial_release_date": "2026-06-16T09:09:33Z",
      "revision_history": [
        {
          "date": "2026-06-16T09:09:33Z",
          "number": "1",
          "summary": "Current version"
        }
      ],
      "status": "final",
      "version": "1"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version",
                "name": "python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch",
                "product": {
                  "name": "python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch",
                  "product_id": "python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
                }
              }
            ],
            "category": "architecture",
            "name": "noarch"
          },
          {
            "branches": [
              {
                "category": "product_name",
                "name": "SUSE Linux Micro 6.1",
                "product": {
                  "name": "SUSE Linux Micro 6.1",
                  "product_id": "SUSE Linux Micro 6.1",
                  "product_identification_helper": {
                    "cpe": "cpe:/o:suse:sl-micro:6.1"
                  }
                }
              }
            ],
            "category": "product_family",
            "name": "SUSE Linux Enterprise"
          }
        ],
        "category": "vendor",
        "name": "SUSE"
      }
    ],
    "relationships": [
      {
        "category": "default_component_of",
        "full_product_name": {
          "name": "python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch as component of SUSE Linux Micro 6.1",
          "product_id": "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
        },
        "product_reference": "python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch",
        "relates_to_product_reference": "SUSE Linux Micro 6.1"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-48522",
      "ids": [
        {
          "system_name": "SUSE CVE Page",
          "text": "https://www.suse.com/security/cve/CVE-2026-48522"
        }
      ],
      "notes": [
        {
          "category": "general",
          "text": "PyJWT is a JSON Web Token implementation in Python. Prior to 2.13.0, PyJWKClient passes its uri argument directly to urllib.request.urlopen() which uses Python stdlib\u0027s default OpenerDirector registering HTTPHandler, HTTPSHandler, FTPHandler, FileHandler, and DataHandler. There is currently no documented option to restrict which schemes PyJWKClient will fetch. If an application\u0027s jku URL ingestion path accepts attacker-influenced URLs (e.g., from JWT header, configuration file, OAuth flow parameter), the attacker can cause PyJWKClient to read arbitrary local files via file:// (SSRF on local filesystem), cause PyJWKClient to attempt FTP / data-URI fetches (broader SSRF surface), or forge tokens that PyJWT verifies as valid. The library does not directly return non-HTTP(S) URI contents to the attacker; the chained \"plant a JWKS to forge tokens\" scenario described in the original report requires additional application-layer flaws (attacker write access to a filesystem path, untrusted jku derivation) that this fix does not address. This vulnerability is fixed in 2.13.0.",
          "title": "CVE description"
        }
      ],
      "product_status": {
        "recommended": [
          "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "CVE-2026-48522",
          "url": "https://www.suse.com/security/cve/CVE-2026-48522"
        },
        {
          "category": "external",
          "summary": "SUSE Bug 1266798 for CVE-2026-48522",
          "url": "https://bugzilla.suse.com/1266798"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or \"zypper patch\".\n",
          "product_ids": [
            "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 4.8,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
            "version": "3.1"
          },
          "products": [
            "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "date": "2026-06-16T09:09:33Z",
          "details": "moderate"
        }
      ],
      "title": "CVE-2026-48522"
    },
    {
      "cve": "CVE-2026-48523",
      "ids": [
        {
          "system_name": "SUSE CVE Page",
          "text": "https://www.suse.com/security/cve/CVE-2026-48523"
        }
      ],
      "notes": [
        {
          "category": "general",
          "text": "PyJWT is a JSON Web Token implementation in Python. From 2.9.0 to 2.12.1, there is a verifier-side algorithm allow-list bypass when jwt.decode() or jwt.decode_complete() are called with a PyJWK key. The token header alg is checked against the caller-supplied algorithms allow-list, but signature verification is performed with the algorithm bound to the PyJWK object instead of the header algorithm. An attacker who controls a registered JWK/JWKS private key can sign with a disallowed algorithm, advertise an allowed algorithm in the JWT header, and still be accepted. The issue affects the documented PyJWKClient.get_signing_key_from_jwt(...) flow. This vulnerability is fixed in 2.13.0.",
          "title": "CVE description"
        }
      ],
      "product_status": {
        "recommended": [
          "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "CVE-2026-48523",
          "url": "https://www.suse.com/security/cve/CVE-2026-48523"
        },
        {
          "category": "external",
          "summary": "SUSE Bug 1266799 for CVE-2026-48523",
          "url": "https://bugzilla.suse.com/1266799"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or \"zypper patch\".\n",
          "product_ids": [
            "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 5.4,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N",
            "version": "3.1"
          },
          "products": [
            "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "date": "2026-06-16T09:09:33Z",
          "details": "moderate"
        }
      ],
      "title": "CVE-2026-48523"
    },
    {
      "cve": "CVE-2026-48524",
      "ids": [
        {
          "system_name": "SUSE CVE Page",
          "text": "https://www.suse.com/security/cve/CVE-2026-48524"
        }
      ],
      "notes": [
        {
          "category": "general",
          "text": "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\u0027s control. This vulnerability is fixed in 2.13.0.",
          "title": "CVE description"
        }
      ],
      "product_status": {
        "recommended": [
          "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "CVE-2026-48524",
          "url": "https://www.suse.com/security/cve/CVE-2026-48524"
        },
        {
          "category": "external",
          "summary": "SUSE Bug 1266800 for CVE-2026-48524",
          "url": "https://bugzilla.suse.com/1266800"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or \"zypper patch\".\n",
          "product_ids": [
            "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 3.7,
            "baseSeverity": "LOW",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L",
            "version": "3.1"
          },
          "products": [
            "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "date": "2026-06-16T09:09:33Z",
          "details": "low"
        }
      ],
      "title": "CVE-2026-48524"
    },
    {
      "cve": "CVE-2026-48525",
      "ids": [
        {
          "system_name": "SUSE CVE Page",
          "text": "https://www.suse.com/security/cve/CVE-2026-48525"
        }
      ],
      "notes": [
        {
          "category": "general",
          "text": "PyJWT is a JSON Web Token implementation in Python. From 2.8.0 to 2.12.1, when verifying detached JWS tokens using the unencoded-payload option (\"b64\": false, RFC 7797), PyJWT performs Base64URL decoding of the compact-serialization payload segment before enforcing the detached-payload rules. For b64=false, PyJWT later discards that decoded payload and replaces it with the caller-provided detached_payload. In practice, this turns the middle segment into an attacker-controlled \u201cwork amplifier\u201d: a remote client can supply an arbitrarily large Base64URL payload segment that forces CPU work + memory allocations even if the signature is invalid. This creates an unauthenticated DoS vector against any endpoint that verifies detached JWS using PyJWT. This vulnerability is fixed in 2.13.0.",
          "title": "CVE description"
        }
      ],
      "product_status": {
        "recommended": [
          "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "CVE-2026-48525",
          "url": "https://www.suse.com/security/cve/CVE-2026-48525"
        },
        {
          "category": "external",
          "summary": "SUSE Bug 1266801 for CVE-2026-48525",
          "url": "https://bugzilla.suse.com/1266801"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or \"zypper patch\".\n",
          "product_ids": [
            "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "products": [
            "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "date": "2026-06-16T09:09:33Z",
          "details": "important"
        }
      ],
      "title": "CVE-2026-48525"
    },
    {
      "cve": "CVE-2026-48526",
      "ids": [
        {
          "system_name": "SUSE CVE Page",
          "text": "https://www.suse.com/security/cve/CVE-2026-48526"
        }
      ],
      "notes": [
        {
          "category": "general",
          "text": "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.",
          "title": "CVE description"
        }
      ],
      "product_status": {
        "recommended": [
          "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "CVE-2026-48526",
          "url": "https://www.suse.com/security/cve/CVE-2026-48526"
        },
        {
          "category": "external",
          "summary": "SUSE Bug 1266802 for CVE-2026-48526",
          "url": "https://bugzilla.suse.com/1266802"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or \"zypper patch\".\n",
          "product_ids": [
            "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 7.4,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
          "products": [
            "SUSE Linux Micro 6.1:python311-PyJWT-2.12.1-slfo.1.1_2.1.noarch"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "date": "2026-06-16T09:09:33Z",
          "details": "important"
        }
      ],
      "title": "CVE-2026-48526"
    }
  ]
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.