Issue summary: An uncommon configuration of clients performing DANE TLSA-based
server authentication, when paired with uncommon server DANE TLSA records, may
result in a use-after-free and/or double-free on the client side.

Impact summary: A use after free can have a range of potential consequences
such as the corruption of valid data, crashes or execution of arbitrary code.

However, the issue only affects clients that make use of TLSA records with both
the PKIX-TA(0/PKIX-EE(1) certificate usages and the DANE-TA(2) certificate
usage.

By far the most common deployment of DANE is in SMTP MTAs for which RFC7672
recommends that clients treat as 'unusable' any TLSA records that have the PKIX
certificate usages. These SMTP (or other similar) clients are not vulnerable
to this issue. Conversely, any clients that support only the PKIX usages, and
ignore the DANE-TA(2) usage are also not vulnerable.

The client would also need to be communicating with a server that publishes a
TLSA RRset with both types of TLSA records.

No FIPS modules are affected by this issue, the problem code is outside the
FIPS module boundary.
Advisories
Source ID Title
Debian DSA Debian DSA DSA-6201-1 openssl security update
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 07 Apr 2026 22:15:00 +0000

Type Values Removed Values Added
Description Issue summary: An uncommon configuration of clients performing DANE TLSA-based server authentication, when paired with uncommon server DANE TLSA records, may result in a use-after-free and/or double-free on the client side. Impact summary: A use after free can have a range of potential consequences such as the corruption of valid data, crashes or execution of arbitrary code. However, the issue only affects clients that make use of TLSA records with both the PKIX-TA(0/PKIX-EE(1) certificate usages and the DANE-TA(2) certificate usage. By far the most common deployment of DANE is in SMTP MTAs for which RFC7672 recommends that clients treat as 'unusable' any TLSA records that have the PKIX certificate usages. These SMTP (or other similar) clients are not vulnerable to this issue. Conversely, any clients that support only the PKIX usages, and ignore the DANE-TA(2) usage are also not vulnerable. The client would also need to be communicating with a server that publishes a TLSA RRset with both types of TLSA records. No FIPS modules are affected by this issue, the problem code is outside the FIPS module boundary.
Title Potential Use-after-free in DANE Client Code
Weaknesses CWE-416
References

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: openssl

Published:

Updated: 2026-04-07T22:00:51.496Z

Reserved: 2026-02-27T13:45:02.161Z

Link: CVE-2026-28387

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-04-07T22:16:20.700

Modified: 2026-04-07T22:16:20.700

Link: CVE-2026-28387

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses