9.8
CRITICAL CVSS 3.1
CVE-2026-57826
openHiTLS X.509 Certificate Chain Verification Improper Authorization Vulnerability
Description

An issue was discovered in openHiTLS 0.2.0 through 0.3.2. In the X.509 certificate chain verification, the basic constraints extension and CA flag processing of intermediate CAs are only verified for v3 certificates, and v1/v2 certificates are ignored.

INFO

Published Date :

Aug. 18, 2026, 8:17 p.m.

Last Modified :

Aug. 31, 2026, 8:59 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-57826 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 CRITICAL 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM 134c704f-9b21-4f2e-91b3-4a467353bcc0
Solution
Update openHiTLS to a version that correctly validates X.509 certificate extensions for all certificate versions.
  • Update openHiTLS to the latest version.
  • Verify certificate validation logic.
  • Deploy updated software.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-57826 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-57826 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-57826 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-57826 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    Aug. 31, 2026

    Action Type Old Value New Value
    Added Reference https://gitcode.com/openHiTLS/openhitls/pull/1399
    Added Reference https://gitcode.com/openHiTLS/openhitls/pull/1657
    Added Reference https://github.com/openHiTLS/openHiTLS/commit/2d3b221d113b452bc197012b185978b8314ee8a4
    Added Reference https://github.com/openHiTLS/openHiTLS/commit/4355cdf5b043d5b9ef698f8f57860f77f8e92561
    Added Reference https://github.com/openHiTLS/openHiTLS/compare/openhitls-0.3.2...openhitls-0.3.3
    Added Reference https://www.openhitls.net/zh/support/HTLS-2026-001.html
    Removed Reference https://gitcode.com/openHiTLS/openhitls/pull/1399
    Removed Reference https://gitcode.com/openHiTLS/openhitls/pull/1657
    Removed Reference https://github.com/openHiTLS/openHiTLS/commit/2d3b221d113b452bc197012b185978b8314ee8a4
    Removed Reference https://github.com/openHiTLS/openHiTLS/commit/4355cdf5b043d5b9ef698f8f57860f77f8e92561
    Removed Reference https://github.com/openHiTLS/openHiTLS/compare/openhitls-0.3.2...openhitls-0.3.3
    Removed Reference https://www.openhitls.net/zh/support/HTLS-2026-001.html
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 31, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
    Removed CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed SSVC {'id': 'CVE-2026-57826', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-19T18:27:38.834575Z'} {'id': 'CVE-2026-57826', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-31T12:26:25.991291Z'}
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 19, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-295
    Added SSVC {'id': 'CVE-2026-57826', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-19T18:27:38.834575Z'}
  • CVE Modified by [email protected]

    Aug. 18, 2026

    Action Type Old Value New Value
    Added Reference https://gitcode.com/openHiTLS/openhitls/pull/1399
    Added Reference https://gitcode.com/openHiTLS/openhitls/pull/1657
    Added Reference https://github.com/openHiTLS/openHiTLS/commit/2d3b221d113b452bc197012b185978b8314ee8a4
    Added Reference https://github.com/openHiTLS/openHiTLS/commit/4355cdf5b043d5b9ef698f8f57860f77f8e92561
  • New CVE Received by [email protected]

    Aug. 18, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'n/a', 'product': 'n/a', 'versions': [{'status': 'affected', 'version': 'n/a'}]}]
    Added Description An issue was discovered in openHiTLS 0.2.0 through 0.3.2. In the X.509 certificate chain verification, the basic constraints extension and CA flag processing of intermediate CAs are only verified for v3 certificates, and v1/v2 certificates are ignored.
    Added Reference https://github.com/openHiTLS/openHiTLS/compare/openhitls-0.3.2...openhitls-0.3.3
    Added Reference https://www.openhitls.net/zh/support/HTLS-2026-001.html
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.