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.
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.
NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.
Note: It is possible that the NVD CVSS may not match that of the CNA. The most common reason for this is that publicly available information does not provide sufficient detail or that information simply was not available at the time the CVSS vector string was assigned.
NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.
Note: NVD Analysts have published a CVSS score for this CVE based on publicly available information at the time of analysis. The CNA has not provided a score within the CVE List.
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OR
*cpe:2.3:a:tlslite-ng_project:tlslite-ng:*:*:*:*:*:*:*:* versions up to (excluding) 0.7.6
*cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha1:*:*:*:*:*:*
*cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha10:*:*:*:*:*:*
*cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha11:*:*:*:*:*:*
*cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha12:*:*:*:*:*:*
*cpe:2.3:a:tlslite-ng_project:tlslite-ng:0.8.0:alpha13:*:*:*:*:*:*
*cpe:2.3:a:tlslite-ng_project:tlslite-
Added
CVSS V2
NIST (AV:N/AC:L/Au:N/C:P/I:N/A:N)
Added
CVSS V3.1
NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Changed
Reference Type
https://github.com/tlsfuzzer/tlslite-ng/commit/c28d6d387bba59d8bd5cb3ba15edc42edf54b368 No Types Assigned
https://github.com/tlsfuzzer/tlslite-ng/commit/c28d6d387bba59d8bd5cb3ba15edc42edf54b368 Patch, Third Party Advisory
Changed
Reference Type
https://github.com/tlsfuzzer/tlslite-ng/pull/438 No Types Assigned
https://github.com/tlsfuzzer/tlslite-ng/pull/438 Patch, Third Party Advisory
Changed
Reference Type
https://github.com/tlsfuzzer/tlslite-ng/pull/439 No Types Assigned
https://github.com/tlsfuzzer/tlslite-ng/pull/439 Patch, Third Party Advisory
Changed
Reference Type
https://github.com/tlsfuzzer/tlslite-ng/security/advisories/GHSA-wvcv-832q-fjg7 No Types Assigned
https://github.com/tlsfuzzer/tlslite-ng/security/advisories/GHSA-wvcv-832q-fjg7 Exploit, Patch, Third Party Advisory
Changed
Reference Type
https://pypi.org/project/tlslite-ng/ No Types Assigned
https://pypi.org/project/tlslite-ng/ Product, Third Party Advisory
Changed
Reference Type
https://securitypitfalls.wordpress.com/2018/08/03/constant-time-compare-in-python/ No Types Assigned
https://securitypitfalls.wordpress.com/2018/08/03/constant-time-compare-in-python/ Exploit, Third Party Advisory
Quick Info
CVE Dictionary Entry: CVE-2020-26263 NVD
Published Date: 12/21/2020 NVD
Last Modified: 12/23/2020
Source: GitHub, Inc.