CVE-2020-26263
Summary
| CVE | CVE-2020-26263 |
|---|---|
| State | PUBLIC |
| Assigner | [email protected] |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2020-12-21 17:15:00 UTC |
| Updated | 2020-12-23 16:09:00 UTC |
| Description | tlslite-ng is an open source python library that implements SSL and TLS cryptographic protocols. In tlslite-ng before versions 0.7.6 and 0.8.0-alpha39, the code that performs decryption and padding check in RSA PKCS#1 v1.5 decryption is data dependant. In particular, the code has multiple ways in which it leaks information about the decrypted ciphertext. It aborts as soon as the plaintext doesn't start with 0x00, 0x02. All TLS servers that enable RSA key exchange as well as applications that use the RSA decryption API directly are vulnerable. This is patched in versions 0.7.6 and 0.8.0-alpha39. Note: the patches depend on Python processing the individual bytes in side-channel free manner, this is known to not the case (see reference). As such, users that require side-channel resistance are recommended to use different TLS implementations, as stated in the security policy of tlslite-ng. |
Risk And Classification
Problem Types: CWE-326
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Tlslite-ng Project | Tlslite-ng | All | All | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha1 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha10 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha11 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha12 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha13 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha14 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha15 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha16 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha17 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha18 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha19 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha2 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha20 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha21 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha22 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha23 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha24 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha25 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha26 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha27 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha28 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha29 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha3 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha30 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha31 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha32 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha33 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha34 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha35 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha36 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha37 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha38 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha4 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha5 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha6 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha7 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha8 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha9 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | All | All | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha1 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha10 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha11 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha12 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha13 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha14 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha15 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha16 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha17 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha18 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha19 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha2 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha20 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha21 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha22 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha23 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha24 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha25 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha26 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha27 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha28 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha29 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha3 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha30 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha31 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha32 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha33 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha34 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha35 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha36 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha37 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha38 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha4 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha5 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha6 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha7 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha8 | All | All |
| Application | Tlslite-ng Project | Tlslite-ng | 0.8.0 | alpha9 | All | All |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| tlslite-ng · PyPI | MISC | pypi.org | Product, Third Party Advisory |
| Bleichenbacher fixes [0.7] by tomato42 · Pull Request #439 · tlsfuzzer/tlslite-ng · GitHub | MISC | github.com | Patch, Third Party Advisory |
| Attempt side-channel free RSA decryption by tomato42 · Pull Request #438 · tlsfuzzer/tlslite-ng · GitHub | MISC | github.com | Patch, Third Party Advisory |
| securitypitfalls.wordpress.com/2018/08/03/constant-time-compare-in-python | MISC | securitypitfalls.wordpress.com | Exploit, Third Party Advisory |
| Merge pull request #439 from tlsfuzzer/bleichenbacher-fixes-0.7 · tlsfuzzer/tlslite-ng@c28d6d3 · GitHub | MISC | github.com | Patch, Third Party Advisory |
| Bleichenbacher timing side-channel oracle in PKCS#1 v1.5 decryption · Advisory · tlsfuzzer/tlslite-ng · GitHub | CONFIRM | github.com | Exploit, Patch, Third Party Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Legacy QID Mappings
- 983233 Python (pip) Security Update for tlslite-ng (GHSA-wvcv-832q-fjg7)