CVE-2020-26154

url.cpp in libproxy through 0.4.15 is prone to a buffer overflow when PAC is enabled, as demonstrated by a large PAC file that is delivered without a Content-length header.

Published: 2020-09-30 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-26154 is rated High Risk (72.7/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 3.53%). EPSS rose +2.81% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-26154

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.72% 3.53% +2.81%
2 2025-11-26 1.58% 0.72% -0.86%
3 2025-11-21 — 1.58% —

Full EPSS history (21 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-26154

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2020-26154

OS Trackers for CVE-2020-26154

vendor priority summary link
alpine critical CVE-2020-26154: 1 source package rows (libproxy); 11 state rows across 9 repos (3.10-main, 3.11-main, 3.17-community, 3.18-community, 3.19-community, 3.20-community, 3.21-community, 3.22-community, edge-community); fixed 7, open 4. https://security.alpinelinux.org/vuln/CVE-2020-26154
debian not yet assigned CVE-2020-26154 not yet assigned priority: Debian including 1 source packages (libproxy), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-26154
redhat medium — https://access.redhat.com/security/cve/CVE-2020-26154
suse high CVE-2020-26154 severity important: SUSE including 358 source package names (0.1.0:libproxy1-0.4.15-4.3.1, 0.1.75:libproxy1-0.4.15-4.3.1, …), 546 product×package rows across 141 product lines (Container caasp/v4/389-ds, Container caasp/v4/busybox, … (141 product lines)): Fixed 385, Known Affected 157, Known Not Affected 4. https://www.suse.com/security/cve/CVE-2020-26154/
ubuntu medium CVE-2020-26154 medium priority: Ubuntu including 1 source packages (libproxy), 6 status rows across 6 suites (bionic, focal, groovy, trusty, upstream, xenial): released 4, DNE 1, needs-triage 1. https://ubuntu.com/security/CVE-2020-26154

Affected software / configurations for CVE-2020-26154

Vendor Product Version Raw CPE
libproxy_project libproxy <= 0.4.15 cpe:2.3:a:libproxy_project:libproxy:*:*:*:*:*:*:*:*
fedoraproject fedora 32 cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
fedoraproject fedora 33 cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
opensuse leap 15.1 cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
opensuse leap 15.2 cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*

References for CVE-2020-26154

cvelogic Threat Intelligence