| 项目 | 详情 | 备注 |
|---|---|---|
| 项目 | https://github.com/layer5io/meshery | |
| 公告日期 | 2021-04-28 | |
| CVE-ID | CVE-2021-31856 | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-31856 |
| EDB-ID | \ | |
| 受影响版本 | v0.5.2 | \ |
| 修复版本 | v0.5.3 | https://github.com/layer5io/meshery/pull/2745 |
| CVSS | 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N | |
| 作者 | https://github.com/ssst0n3 |
meshery/models/meshery_pattern_persister.go中的GetMesheryPatterns()函数存在SQL注入漏洞，通过/api/experimental/patternfile?order=id%3Bselect(randomblob(1000000000))&page=0&page_size=0的order参数。
http://<IP>:9081/api/experimental/patternfile?order=id%3Bselect(randomblob(1000000000))&page=0&page_size=0
函数GetMesheryPatterns中的参数order是一个字符串实例。在使用gorm时，它会被直接追加到查询语句中，并且sql查询语句由Find()执行。
https://github.com/layer5io/meshery/blob/v0.5.2/models/meshery_pattern_persister.go#L35
func (mpp *MesheryPatternPersister) GetMesheryPatterns(search, order string, page, pageSize uint64) ([]byte, error) {
if order == "" {
order = "updated_at desc"
}
...
query := mpp.DB.Order(order)
...
Paginate(uint(page), uint(pageSize))(query).Find(&patterns)
...
}
如果参数order来自用户输入且未经任何过滤，则存在SQL注入漏洞。
追踪调用过程，可以发现参数"order"直接来自查询。
https://github.com/layer5io/meshery/blob/v0.5.2/handlers/meshery_pattern_handler.go#L140
func (h *Handler) GetMesheryPatternsHandler(
rw http.ResponseWriter,
r *http.Request,
prefObj *models.Preference,
user *models.User,
provider models.Provider,
) {
q := r.URL.Query()
resp, err := provider.GetMesheryPatterns(r, q.Get("page"), q.Get("page_size"), q.Get("search"), q.Get("order"))
if err != nil {
http.Error(rw, fmt.Sprintf("failed to fetch the patterns: %s", err), http.StatusInternalServerError)
return
}
rw.Header().Set("Content-Type", "application/json")
fmt.Fprint(rw, string(resp))
}
如果进行调试，可以发现查询语句为：
SELECT * FROM `meshery_patterns` ORDER BY <ORDER>
如果我们让order=id;drop table meshery_patterns，该语句将变成
SELECT * FROM `meshery_patterns` ORDER BY id;drop table meshery_patterns
并且该表将被删除。
完整的调用链为：
https://github.com/layer5io/meshery/blob/v0.5.2/router/server.go#L127
gMux.Handle("/api/experimental/patternfile", h.ProviderMiddleware(h.AuthMiddleware(h.SessionInjectorMiddleware(h.PatternFileRequestHandler)))).
Methods("POST", "GET")
https://github.com/layer5io/meshery/blob/v0.5.2/handlers/meshery_pattern_handler.go#L93
func (h *Handler) PatternFileRequestHandler(
...
h.GetMesheryPatternsHandler(rw, r, prefObj, user, provider)
}
https://github.com/layer5io/meshery/blob/v0.5.2/handlers/meshery_pattern_handler.go#L149
func (h *Handler) GetMesheryPatternsHandler(
...
resp, err := provider.GetMesheryPatterns(r, q.Get("page"), q.Get("page_size"), q.Get("search"), q.Get("order"))
..
https://github.com/layer5io/meshery/blob/v0.5.2/models/default_local_provider.go#L439
func (l *DefaultLocalProvider) GetMesheryPatterns(req *http.Request, page, pageSize, search, order string) ([]byte, error) {
...
return l.MesheryPatternPersister.GetMesheryPatterns(search, order, pg, pgs)
}
https://github.com/layer5io/meshery/blob/v0.5.2/models/meshery_pattern_persister.go#L35-L44
func (mpp *MesheryPatternPersister) GetMesheryPatterns(search, order string, page, pageSize uint64) ([]byte, error) {
if order == "" {
order = "updated_at desc"
}
...
query := mpp.DB.Order(order)
...
Paginate(uint(page), uint(pageSize))(query).Find(&patterns)
...
}
为参数order设置白名单，而不是直接使用未经任何过滤的用户输入参数。
https://github.com/layer5io/meshery/pull/2745
你可以从gorm的文档中获取一些参考：https://gorm.io/docs/security.html