Bug 2538346 (CVE-2026-75883)

Summary: CVE-2026-75883 pppd: pppd: Buffer overflow in PEAP response handling leads to data corruption or denial of service.
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in pppd. A remote attacker could exploit a buffer overflow vulnerability in the PEAP response handling. By sending a specially crafted PEAP Request packet, an attacker could cause the pppd process to corrupt global static data, leading to incorrect behavior or a system crash.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-22 18:12:20 UTC 
The code in pppd that formats a response to a PEAP Request packet in peap_response() copies an entire TLS record of up to 16384 bytes into the fixed global buffer outpacket_buf
 without checking the available space and without implementing outgoing 
PEAP fragmentation. Thus a pppd process connecting to a server which 
requests PEAP authentication can be induced to corrupt global static 
data following the outpacket_buf array, most likely causing incorrect behavior or a crash.