Bug 2494220

Summary: CVE-2026-27145 spoofdpi: golang crypto/x509: Denial of Service via excessive processing of DNS SAN entries [epel-all]
Product: [Fedora] Fedora EPEL Reporter: jkelly <jkelly>
Component: spoofdpiAssignee: Emir Akdag <infraw.linux>
Status: CLOSED ERRATA QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: epel10CC: go-sig, infraw.linux
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["1765a0c8-adb1-4223-88bf-d35a230e256a"]}
Fixed In Version: spoofdpi-1.5.3-1.fc45 spoofdpi-1.5.3-1.fc44 spoofdpi-1.5.3-1.el9 spoofdpi-1.5.3-1.el10_3 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-07-14 15:44:57 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2484207    

Description jkelly 2026-06-29 14:11:43 UTC
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

(*x509.Certificate).VerifyHostname previously called matchHostnames in a loop over all DNS Subject Alternative Name (SAN) entries. This caused strings.Split(host, ".") to execute repeatedly on the same input hostname. With a large DNS SAN list, verification costs scaled quadratically based on the number of SAN entries multiplied by the hostname's label count. Because x509.Verify validates hostnames before building the certificate chain, this overhead occurred even for untrusted certificates.

Comment 1 Fedora Update System 2026-07-14 10:23:49 UTC
FEDORA-2026-812049f95c (spoofdpi-1.5.3-1.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-812049f95c

Comment 2 Fedora Update System 2026-07-14 10:24:44 UTC
FEDORA-EPEL-2026-09c2d23aa6 (spoofdpi-1.5.3-1.el10_3) has been submitted as an update to Fedora EPEL 10.3.
https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-09c2d23aa6

Comment 3 Fedora Update System 2026-07-14 10:25:36 UTC
FEDORA-EPEL-2026-9214d617c1 (spoofdpi-1.5.3-1.el9) has been submitted as an update to Fedora EPEL 9.
https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-9214d617c1

Comment 4 Fedora Update System 2026-07-14 14:31:35 UTC
FEDORA-2026-b382f3a576 (spoofdpi-1.5.3-1.fc45) has been submitted as an update to Fedora 45.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-b382f3a576

Comment 5 Fedora Update System 2026-07-14 15:44:57 UTC
FEDORA-2026-b382f3a576 (spoofdpi-1.5.3-1.fc45) has been pushed to the Fedora 45 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 6 Fedora Update System 2026-07-15 00:32:48 UTC
FEDORA-EPEL-2026-9214d617c1 has been pushed to the Fedora EPEL 9 testing repository.

You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-9214d617c1

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 7 Fedora Update System 2026-07-15 01:10:28 UTC
FEDORA-EPEL-2026-09c2d23aa6 has been pushed to the Fedora EPEL 10.3 testing repository.

You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-09c2d23aa6

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 8 Fedora Update System 2026-07-15 01:24:20 UTC
FEDORA-2026-812049f95c has been pushed to the Fedora 44 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-812049f95c`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-812049f95c

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 9 Fedora Update System 2026-07-18 00:26:46 UTC
FEDORA-2026-812049f95c (spoofdpi-1.5.3-1.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 10 Fedora Update System 2026-07-18 00:42:18 UTC
FEDORA-EPEL-2026-9214d617c1 (spoofdpi-1.5.3-1.el9) has been pushed to the Fedora EPEL 9 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 11 Fedora Update System 2026-07-18 00:42:22 UTC
FEDORA-EPEL-2026-09c2d23aa6 (spoofdpi-1.5.3-1.el10_3) has been pushed to the Fedora EPEL 10.3 stable repository.
If problem still persists, please make note of it in this bug report.