Buffer overflow in Ppp Project

CVE-2026-75883

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.

Vulnerability class: Buffer Overflow

CVSS v3 metric

CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-75883?
CVE-2026-75883 is a medium-severity vulnerability in Ppp Project, classified under Heap-based Buffer Overflow. CVSS score: 6.8/10. Published 2026-09-18.
How severe is CVE-2026-75883?
Medium severity. CVSS v3 base score is 6.8 out of 10.