Bug 2540947

Summary: CVE-2026-88383 libical: libical: Denial of Service via crafted iCalendar property parsing [fedora-all]
Product: [Fedora] Fedora Reporter: Vladimir Vasilev <vvasilev>
Component: libicalAssignee: Milan Crha <mcrha>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: mcrha
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["8eb94dbe-16d5-426c-8b45-6b728eca1a90"]}
Fixed In Version: libical-3.0.20-8.fc44 libical-3.0.20-5.fc43 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-10-07 01:38:48 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: 2540578    

Description Vladimir Vasilev 2026-09-25 05:35:23 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.

libical 4.0.6 contains an incompatible function pointer in icalparameter_string_to_kind(). When parsing iCalendar data containing a parameterized property, the function passes icalparameter_compare_kind_map() to bsearch() through an incompatible comparator function pointer type. bsearch() invokes the callback through the mismatched type, resulting in undefined behavior and process termination, leading to denial of service.

Comment 1 Milan Crha 2026-09-25 06:18:23 UTC
The fix [1] is not released yet. Nonetheless Fedora is still in the 3.x series, not 4.x series (it's awaiting approval), thus, as it is in the time of writing this comment, the Fedora is unaffected by it.

[1] https://github.com/libical/libical/issues/1361

Comment 2 Milan Crha 2026-09-25 06:19:48 UTC
(In reply to Milan Crha from comment #1)
> Nonetheless Fedora is still in the 3.x series, not 4.x series (it's awaiting approval),
> thus, as it is in the time of writing this comment, the Fedora is unaffected by it.

Ehm, or not, I just checked and the 3.x series has the same code.

Comment 3 Fedora Update System 2026-09-25 07:14:56 UTC
FEDORA-2026-9616ace61b (libical-3.0.20-10.fc45) has been submitted as an update to Fedora 45.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-9616ace61b

Comment 4 Fedora Update System 2026-09-25 07:15:37 UTC
FEDORA-2026-a76bba1412 (libical-3.0.20-8.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-a76bba1412

Comment 5 Fedora Update System 2026-09-25 07:16:10 UTC
FEDORA-2026-d4c8dad1fd (libical-3.0.20-5.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-d4c8dad1fd

Comment 6 Fedora Update System 2026-09-26 01:47:35 UTC
FEDORA-2026-9616ace61b has been pushed to the Fedora 45 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-9616ace61b`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-9616ace61b

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

Comment 7 Fedora Update System 2026-09-26 02:04:05 UTC
FEDORA-2026-a76bba1412 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-a76bba1412`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-a76bba1412

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

Comment 8 Fedora Update System 2026-09-26 02:27:23 UTC
FEDORA-2026-d4c8dad1fd has been pushed to the Fedora 43 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-d4c8dad1fd`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-d4c8dad1fd

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

Comment 9 Fedora Update System 2026-10-07 01:38:48 UTC
FEDORA-2026-a76bba1412 (libical-3.0.20-8.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 2026-10-12 01:15:08 UTC
FEDORA-2026-d4c8dad1fd (libical-3.0.20-5.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 11 Fedora Update System 2026-10-21 01:59:10 UTC
FEDORA-2026-9616ace61b has been pushed to the Fedora 45 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-9616ace61b`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-9616ace61b

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