CVE-2020-26154
libproxy: sending more than 102400 bytes in PAC without a Content-Length present could result in buffer overflow
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · July 16, 2020
Updated · March 18, 2026
Description
A vulnerability was found in libproxy, where a buffer overflow can occur if a server serving a PAC file sends more than 102400 bytes without a Content-Length header, this flaw allows an attacker to trigger an overflow of PAC_HTTP_BLOCK_SIZE (512 bytes), potentially leading to application crashes or unexpected behavior when processing large PAC files.
Statement
This vulnerability is rated as moderate because libproxy can overflow its buffer by PAC_HTTP_BLOCK_SIZE (512 bytes) if a server serving a PAC file sends more than 102400 bytes without a Content-Length header, specific conditions related to PAC file handling, and while it could lead to crashes or unexpected behavior, its overall impact is limited.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 7.5CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE-121 · Stack-based Buffer Overflow