CVE-2018-1000159

Name: CVE-2018-1000159
Creator: NVD / NIST
Published: 2018-04-18T19:29:00.333+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

UnknownEPSS 0.79%

Last modified Jun 17, 2026

CVE-2018-1000159 is a vulnerability of currently unknown severity. tlslite-ng version 0.7.3 and earlier, since 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. EPSS estimates a 0.79% chance of exploitation in the next 30 days.

Description

tlslite-ng version 0.7.3 and earlier, since 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.

Metrics

EPSS Probability

0.79%

51.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-354

Affected Software

Vendor	Product	Versions
Tlslite-Ng Project	Tlslite-Ng	<= 0.7.3

References

https://github.com/tomato42/tlslite-ng/pull/234Third Party Advisory
https://github.com/tomato42/tlslite-ng/pull/234Third Party Advisory

Timeline

Published: Apr 18, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-1000159?

How severe is CVE-2018-1000159?

Severity scoring for CVE-2018-1000159 is pending analysis. The EPSS model estimates a 0.79% probability of exploitation in the next 30 days.

How do I fix CVE-2018-1000159?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-1000159?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST