GHSA-cwh5-3cw7-4286
tlslite-ng off-by-one error on mac checking
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| PyPI | tlslite-ng | < 0.7.4 | 0.7.4 |
Details
As written in the advisory (Markdown source, shown as plain text).
tlslite-ng version 0.7.3 and earlier, since commit [d7b288316bca7bcdd082e6ccff5491e241305233](https://github.com/tlsfuzzer/tlslite-ng/commit/d7b288316bca7bcdd082e6ccff5491e241305233) contains a CWE-354: Improper Validation of Integrity Check Value vulnerability in TLS implementation, `tlslite/utils/constanttime.py`: `ct_check_cbc_mac_and_pad()`; line `end_pos = data_len - 1 - mac.digest_size` that can result in an attacker manipulating the TLS ciphertext which will not be detected by receiving tlslite-ng. This attack appears to be exploitable via man in the middle on a network connection. This vulnerability appears to have been fixed after commit [3674815d1b0f7484454995e2737a352e0a6a93d8](https://github.com/tlsfuzzer/tlslite-ng/pull/234/commits/3674815d1b0f7484454995e2737a352e0a6a93d8).
References
External links from the advisory. They lead to third-party sites.
- https://nvd.nist.gov/vuln/detail/CVE-2018-1000159
- https://github.com/tlsfuzzer/tlslite-ng/pull/234/commits/3674815d1b0f7484454995e2737a352e0a6a93d8
- https://github.com/tomato42/tlslite-ng/pull/234
- https://github.com/tlsfuzzer/tlslite-ng/commit/d7b288316bca7bcdd082e6ccff5491e241305233
- https://github.com/pypa/advisory-database/tree/main/vulns/tlslite-ng/PYSEC-2018-31.yaml
- https://github.com/tomato42/tlslite-ng