SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2018-1000159

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();…

MEDIUM 5.9EPSS 0.77%

Does this matter?

Lower severity and a low EPSS score (0.77%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.0
5.9 MEDIUMCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS
0.77% probability · 55th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-354
Affected
tlslite-ng project/tlslite-ng
Source
cve@mitre.org
EPSS trend
0%3%5%27 October 2026: 0.77%27 October 202627 October 2026

EPSS 0.8% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.