CVE-2020-262637.5HighCWE-326

CVE-2020-26263: RSA vulnerability in tslite-ng

tlsfuzzer · tlslite-ng

Affected: tlsfuzzer tlslite-ng · Exploitation: possible (1 to 10%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

1.5%probability of exploitation in the next 30 days

75th percentile

050100

Higher than 75% of scored CVEs

7.5HighCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

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.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

tlsfuzzer · tlslite-ng< 0.7.6; >= 0.8.0-alpha1, < 0.8.0-alpha39

On the Atlas

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Open the Atlas

Exploitation: Possible (1 to 10%). EPSS between 1% and 10%.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Inadequate Encryption Strength · Cryptography
Published: December 2020
Band: Possible (1 to 10%), December 2020

CoverageNo articles yet

No CyberSIXT article names CVE-2020-26263 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.