Bug 2552481

Summary: CVE-2026-35189 edk2: openssl: Denial of Service via excessive memory allocation in CRL distribution point processing [fedora-all]
Product: [Fedora] Fedora Reporter: Srikanth Balasubramanian <sbalasub>
Component: edk2Assignee: Paolo Bonzini <pbonzini>
Status: CLOSED CURRENTRELEASE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: low Docs Contact:
Priority: low    
Version: rawhideCC: berrange, crobinso, kraxel, pbonzini, virt-maint
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["9a7f0282-f682-468b-b141-d4f6639b551d"]}
Fixed In Version: Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-10-15 08:24:26 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: 2543242    

Description Srikanth Balasubramanian 2026-10-14 17:07:23 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.

Issue summary: A certificate with many nameRelativeToCRLIssuer CRL
distribution points causes disproportionate heap growth when OpenSSL caches
X.509 extensions.

Impact summary: Receiving a crafted certificate from a malicious peer can lead
to significant memory pressure and possible Denial of Service in clients or
in servers that solicit client certificates.

CWE: CWE-770: Allocation of Resources Without Limits or Throttling

Description: A certificate or a set of certificates that fits under the limit for
size of certificates accepted from the peer (~100 KiB) can result in allocation
of several hundred MiB of resident memory on the receiving side
during a normal TLS handshake.  This may be enough to crash the client or
server, if multiple concurrent connections lead to similarly large memory
allocations.

The fix postpones processing of the CRL distribution points extensions in
certificates to the time when the processed value is required for CRL processing.
This avoids keeping large memory allocations for a long time when such
certificates are received.

FIPS impact: no
The affected code is outside the FIPS module boundary.
Comment 1 Gerd Hoffmann 2026-10-15 08:24:26 UTC 
edk2 has been updated to use openssl-3.5.9 already which includes the fix.