sigstore timestamp-authority up to 2.0.5 certificate validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.8$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in sigstore timestamp-authority up to 2.0.5. Impacted is an unknown function. Such manipulation leads to certificate validation. This vulnerability is documented as CVE-2026-39984. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in sigstore timestamp-authority up to 2.0.5 and classified as critical. Affected by this issue is some unknown functionality. The manipulation with an unknown input leads to a certificate validation vulnerability. Using CWE to declare the problem leads to CWE-295. The product does not validate, or incorrectly validates, a certificate. Impacted is confidentiality, integrity, and availability.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-39984. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1587.003.

The vulnerability scanner Nessus provides a plugin with the ID 311219 (Amazon Linux 2 : nerdctl, --advisory ALAS2-2026-3265 (ALAS-2026-3265)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.0.6 eliminates this vulnerability.

The vulnerability is also documented in the databases at CNNVD (CNNVD-202604-3300), Tenable (311219) and EUVD (EUVD-2026-22813). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.0
VulDB Meta Temp Score: 4.8

VulDB Base Score: 5.0
VulDB Temp Score: 4.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Certificate validation
CWE: CWE-295 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 311219
Nessus Name: Amazon Linux 2 : nerdctl, --advisory ALAS2-2026-3265 (ALAS-2026-3265)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: timestamp-authority 2.0.6

Timelineinfo

04/14/2026 Advisory disclosed
04/14/2026 +0 days VulDB entry created
05/01/2026 +16 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-39984 (🔒)
GCVE (CVE): GCVE-0-2026-39984
GCVE (VulDB): GCVE-100-357296
EUVD: 🔒
CNNVD: CNNVD-202604-3300 - Sigstore Timestamp Authority 安全漏洞

Entryinfo

Created: 04/14/2026 09:29
Updated: 05/01/2026 01:54
Changes: 04/14/2026 09:29 (51), 04/15/2026 06:40 (1), 04/16/2026 20:56 (6), 05/01/2026 01:54 (2)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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