CVE-2013-2503

mediumpriority · track · 35EPSS 0.046 · 92 %ileexploit · functionalEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · functional

Likely / severe?

4.63% (92nd) EPSS

CVSS 5.8 · medium

Is it mine?

30 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

Privoxy before 3.0.21 does not properly handle Proxy-Authenticate and Proxy-Authorization headers in the client-server data stream, which makes it easier for remote HTTP servers to spoof the intended proxy service via a 407 (aka Proxy Authentication Required) HTTP status code.

cvss

Technical severity, 0–10. One row per scoring source.

5.8

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.05.8mediumAV:N/AC:M/Au:N/C:P/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 4.9

v2.05.2mediumAV:N/AC:M/Au:N/C:P/I:P/A:N/E:POCsecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimary

exploits (1)

Public proof-of-concept and weaponised exploit code.

EDB-38377Privoxy Proxy - Authentication Information Disclosurefunctional · exploit_db

affected products (30)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
privoxy privoxy≤ 3.0.20nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 2.9.0nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 2.9.1nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 2.9.11nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 2.9.12nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 2.9.13nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 2.9.14nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 2.9.16nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 2.9.18nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 2.9.2nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 2.9.3nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 3.0nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 3.0.10nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 3.0.11nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 3.0.12nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 3.0.13nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 3.0.14nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 3.0.15nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*
privoxy privoxy= 3.0.16nvdUScpe:2.3:a:privoxy:privoxy:*:*:*:*:*:*:*:*

showing 20 of 30

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2013-03-11modified 2026-06-16

related (25,202)

Related entries.

ID	severity	EPSS	exploitable	published
CVE-2026-88771US	critical9.8OT critical	82.2% (100th)	KEV	2026-09-27
Improper input validation vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS,…
CVE-2026-93952US	—OT critical	1.38% (72nd)	KEV	2026-09-22
VeloCloud Orchestrator (VCO) on-prem has a security issue where this issue may allow a remote attacker to access privileged internal functionality and impact the VCO host. Successf…
CVE-2026-12569US	critical9.8OT critical	46.0% (99th)	KEV	2026-06-18
A critical remote code execution (RCE) vulnerability has been reported in PTC Windchill PDMlink and PTC FlexPLM. The vulnerability may be exploited through the deserialization of u…
CVE-2026-34910US	—OT critical	90.0% (100th)	KEV	2026-05-22
A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS devices to execute a Command Injection.
CVE-2026-6973US	—OT critical	34.5% (98th)	KEV	2026-05-07
An Improper Input Validation in Ivanti EPMM before versions 12.6.1.1, 12.7.0.1, and 12.8.0.1 allows a remotely authenticated user with administrative access to achieve remote code…

+25197 more

references (8)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan