6.5
MEDIUM
CVE-2020-15811
Squid HTTP Request Splitting Cache Poisoning
Description

An issue was discovered in Squid before 4.13 and 5.x before 5.0.4. Due to incorrect data validation, HTTP Request Splitting attacks may succeed against HTTP and HTTPS traffic. This leads to cache poisoning. This allows any client, including browser scripts, to bypass local security and poison the browser cache and any downstream caches with content from an arbitrary source. Squid uses a string search instead of parsing the Transfer-Encoding header to find chunked encoding. This allows an attacker to hide a second request inside Transfer-Encoding: it is interpreted by Squid as chunked and split out into a second request delivered upstream. Squid will then deliver two distinct responses to the client, corrupting any downstream caches.

INFO

Published Date :

Sept. 2, 2020, 5:15 p.m.

Last Modified :

Feb. 2, 2024, 3:04 a.m.

Source :

[email protected]

Remotely Exploitable :

Yes !

Impact Score :

3.6

Exploitability Score :

2.8
Public PoC/Exploit Available at Github

CVE-2020-15811 has a 1 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

Affected Products

The following products are affected by CVE-2020-15811 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Canonical ubuntu_linux
1 Fedoraproject fedora
1 Debian debian_linux
1 Opensuse leap
1 Squid-cache squid
: Total Affected Vendor : 5 | Products : 5
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2020-15811.

URL Resource
http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00012.html Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00017.html Mailing List Third Party Advisory
https://github.com/squid-cache/squid/security/advisories/GHSA-c7p8-xqhm-49wv Patch
https://lists.debian.org/debian-lts-announce/2020/10/msg00005.html Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BE6FKUN7IGTIR2MEEMWYDT7N5EJJLZI2/ Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BMTFLVB7GLRF2CKGFPZ4G4R5DIIPHWI3/ Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HJJDI7JQFGQLVNCKMVY64LAFMKERAOK7/ Mailing List Third Party Advisory
https://security.netapp.com/advisory/ntap-20210219-0007/ Third Party Advisory
https://security.netapp.com/advisory/ntap-20210226-0006/ Third Party Advisory
https://security.netapp.com/advisory/ntap-20210226-0007/ Broken Link Third Party Advisory
https://usn.ubuntu.com/4477-1/ Third Party Advisory
https://usn.ubuntu.com/4551-1/ Third Party Advisory
https://www.debian.org/security/2020/dsa-4751 Mailing List Third Party Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

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404notf0und/CVE-Flow

CVE Data Analysis, CVE Monitor, CVE EXP Prediction Based on Deep Learning. 1999-2020年存量CVE数据分析、监控CVE增量更新、基于深度学习的CVE EXP预测和自动化推送

Python

Updated: 2 weeks, 5 days ago
176 stars 24 fork 24 watcher
Born at : June 15, 2020, 2:56 p.m. This repo has been linked 692 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2020-15811 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2020-15811 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Modified Analysis by [email protected]

    Feb. 02, 2024

    Action Type Old Value New Value
    Changed Reference Type https://github.com/squid-cache/squid/security/advisories/GHSA-c7p8-xqhm-49wv Patch, Third Party Advisory https://github.com/squid-cache/squid/security/advisories/GHSA-c7p8-xqhm-49wv Patch
    Changed Reference Type https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BE6FKUN7IGTIR2MEEMWYDT7N5EJJLZI2/ No Types Assigned https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BE6FKUN7IGTIR2MEEMWYDT7N5EJJLZI2/ Mailing List, Third Party Advisory
    Changed Reference Type https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BMTFLVB7GLRF2CKGFPZ4G4R5DIIPHWI3/ No Types Assigned https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BMTFLVB7GLRF2CKGFPZ4G4R5DIIPHWI3/ Mailing List, Third Party Advisory
    Changed Reference Type https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HJJDI7JQFGQLVNCKMVY64LAFMKERAOK7/ No Types Assigned https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HJJDI7JQFGQLVNCKMVY64LAFMKERAOK7/ Mailing List, Third Party Advisory
    Changed Reference Type https://security.netapp.com/advisory/ntap-20210226-0007/ Third Party Advisory https://security.netapp.com/advisory/ntap-20210226-0007/ Broken Link, Third Party Advisory
    Changed Reference Type https://www.debian.org/security/2020/dsa-4751 Third Party Advisory https://www.debian.org/security/2020/dsa-4751 Mailing List, Third Party Advisory
    Removed CWE NIST CWE-444
    Added CWE NIST CWE-697
  • CVE Modified by [email protected]

    Nov. 07, 2023

    Action Type Old Value New Value
    Added Reference MITRE https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HJJDI7JQFGQLVNCKMVY64LAFMKERAOK7/ [No types assigned]
    Added Reference MITRE https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BMTFLVB7GLRF2CKGFPZ4G4R5DIIPHWI3/ [No types assigned]
    Added Reference MITRE https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BE6FKUN7IGTIR2MEEMWYDT7N5EJJLZI2/ [No types assigned]
    Removed Reference MITRE https://lists.fedoraproject.org/archives/list/[email protected]/message/HJJDI7JQFGQLVNCKMVY64LAFMKERAOK7/
    Removed Reference MITRE https://lists.fedoraproject.org/archives/list/[email protected]/message/BMTFLVB7GLRF2CKGFPZ4G4R5DIIPHWI3/
    Removed Reference MITRE https://lists.fedoraproject.org/archives/list/[email protected]/message/BE6FKUN7IGTIR2MEEMWYDT7N5EJJLZI2/
  • Modified Analysis by [email protected]

    Mar. 04, 2021

    Action Type Old Value New Value
    Changed Reference Type http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00012.html Third Party Advisory http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00012.html Mailing List, Third Party Advisory
    Changed Reference Type http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00017.html Third Party Advisory http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00017.html Mailing List, Third Party Advisory
    Changed Reference Type https://lists.debian.org/debian-lts-announce/2020/10/msg00005.html No Types Assigned https://lists.debian.org/debian-lts-announce/2020/10/msg00005.html Mailing List, Third Party Advisory
    Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/BE6FKUN7IGTIR2MEEMWYDT7N5EJJLZI2/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/BE6FKUN7IGTIR2MEEMWYDT7N5EJJLZI2/ Mailing List, Third Party Advisory
    Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/BMTFLVB7GLRF2CKGFPZ4G4R5DIIPHWI3/ Third Party Advisory https://lists.fedoraproject.org/archives/list/[email protected]/message/BMTFLVB7GLRF2CKGFPZ4G4R5DIIPHWI3/ Mailing List, Third Party Advisory
    Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/HJJDI7JQFGQLVNCKMVY64LAFMKERAOK7/ Third Party Advisory https://lists.fedoraproject.org/archives/list/[email protected]/message/HJJDI7JQFGQLVNCKMVY64LAFMKERAOK7/ Mailing List, Third Party Advisory
    Changed Reference Type https://security.netapp.com/advisory/ntap-20210219-0007/ No Types Assigned https://security.netapp.com/advisory/ntap-20210219-0007/ Third Party Advisory
    Changed Reference Type https://security.netapp.com/advisory/ntap-20210226-0006/ No Types Assigned https://security.netapp.com/advisory/ntap-20210226-0006/ Third Party Advisory
    Changed Reference Type https://security.netapp.com/advisory/ntap-20210226-0007/ No Types Assigned https://security.netapp.com/advisory/ntap-20210226-0007/ Third Party Advisory
    Changed Reference Type https://usn.ubuntu.com/4551-1/ No Types Assigned https://usn.ubuntu.com/4551-1/ Third Party Advisory
    Changed CPE Configuration OR *cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:* OR *cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* *cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* *cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
    Changed CPE Configuration OR *cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* *cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* *cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* *cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:* *cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:* OR *cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* *cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
    Added CPE Configuration OR *cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* *cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* *cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
    Added CPE Configuration OR *cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:* *cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Feb. 26, 2021

    Action Type Old Value New Value
    Added Reference https://security.netapp.com/advisory/ntap-20210226-0006/ [No Types Assigned]
    Added Reference https://security.netapp.com/advisory/ntap-20210226-0007/ [No Types Assigned]
  • CVE Modified by [email protected]

    Feb. 19, 2021

    Action Type Old Value New Value
    Added Reference https://security.netapp.com/advisory/ntap-20210219-0007/ [No Types Assigned]
  • CVE Modified by [email protected]

    Oct. 02, 2020

    Action Type Old Value New Value
    Added Reference https://lists.debian.org/debian-lts-announce/2020/10/msg00005.html [No Types Assigned]
  • CVE Modified by [email protected]

    Sep. 30, 2020

    Action Type Old Value New Value
    Added Reference https://usn.ubuntu.com/4551-1/ [No Types Assigned]
  • CVE Modified by [email protected]

    Sep. 25, 2020

    Action Type Old Value New Value
    Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/BE6FKUN7IGTIR2MEEMWYDT7N5EJJLZI2/ [No Types Assigned]
  • Initial Analysis by [email protected]

    Sep. 11, 2020

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:S/C:N/I:P/A:N)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
    Changed Reference Type http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00012.html No Types Assigned http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00012.html Third Party Advisory
    Changed Reference Type http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00017.html No Types Assigned http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00017.html Third Party Advisory
    Changed Reference Type https://github.com/squid-cache/squid/security/advisories/GHSA-c7p8-xqhm-49wv No Types Assigned https://github.com/squid-cache/squid/security/advisories/GHSA-c7p8-xqhm-49wv Patch, Third Party Advisory
    Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/BMTFLVB7GLRF2CKGFPZ4G4R5DIIPHWI3/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/BMTFLVB7GLRF2CKGFPZ4G4R5DIIPHWI3/ Third Party Advisory
    Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/HJJDI7JQFGQLVNCKMVY64LAFMKERAOK7/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/HJJDI7JQFGQLVNCKMVY64LAFMKERAOK7/ Third Party Advisory
    Changed Reference Type https://usn.ubuntu.com/4477-1/ No Types Assigned https://usn.ubuntu.com/4477-1/ Third Party Advisory
    Changed Reference Type https://www.debian.org/security/2020/dsa-4751 No Types Assigned https://www.debian.org/security/2020/dsa-4751 Third Party Advisory
    Added CWE NIST CWE-444
    Added CPE Configuration OR *cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:* versions up to (excluding) 4.13 *cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:* versions from (including) 5.0 up to (excluding) 5.0.4
    Added CPE Configuration OR *cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
    Added CPE Configuration OR *cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* *cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* *cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* *cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:* *cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*
  • CVE Modified by [email protected]

    Sep. 07, 2020

    Action Type Old Value New Value
    Added Reference http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00017.html [No Types Assigned]
  • CVE Modified by [email protected]

    Sep. 05, 2020

    Action Type Old Value New Value
    Added Reference http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00012.html [No Types Assigned]
  • CVE Modified by [email protected]

    Sep. 03, 2020

    Action Type Old Value New Value
    Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/BMTFLVB7GLRF2CKGFPZ4G4R5DIIPHWI3/ [No Types Assigned]
  • CVE Modified by [email protected]

    Sep. 03, 2020

    Action Type Old Value New Value
    Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/HJJDI7JQFGQLVNCKMVY64LAFMKERAOK7/ [No Types Assigned]
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2020-15811 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2020-15811 weaknesses.

CAPEC-3: Using Leading 'Ghost' Character Sequences to Bypass Input Filters Using Leading 'Ghost' Character Sequences to Bypass Input Filters CAPEC-6: Argument Injection Argument Injection CAPEC-7: Blind SQL Injection Blind SQL Injection CAPEC-8: Buffer Overflow in an API Call Buffer Overflow in an API Call CAPEC-9: Buffer Overflow in Local Command-Line Utilities Buffer Overflow in Local Command-Line Utilities CAPEC-10: Buffer Overflow via Environment Variables Buffer Overflow via Environment Variables CAPEC-14: Client-side Injection-induced Buffer Overflow Client-side Injection-induced Buffer Overflow CAPEC-15: Command Delimiters Command Delimiters CAPEC-24: Filter Failure through Buffer Overflow Filter Failure through Buffer Overflow CAPEC-41: Using Meta-characters in E-mail Headers to Inject Malicious Payloads Using Meta-characters in E-mail Headers to Inject Malicious Payloads CAPEC-43: Exploiting Multiple Input Interpretation Layers Exploiting Multiple Input Interpretation Layers CAPEC-44: Overflow Binary Resource File Overflow Binary Resource File CAPEC-45: Buffer Overflow via Symbolic Links Buffer Overflow via Symbolic Links CAPEC-46: Overflow Variables and Tags Overflow Variables and Tags CAPEC-47: Buffer Overflow via Parameter Expansion Buffer Overflow via Parameter Expansion CAPEC-52: Embedding NULL Bytes Embedding NULL Bytes CAPEC-53: Postfix, Null Terminate, and Backslash Postfix, Null Terminate, and Backslash CAPEC-64: Using Slashes and URL Encoding Combined to Bypass Validation Logic Using Slashes and URL Encoding Combined to Bypass Validation Logic CAPEC-67: String Format Overflow in syslog() String Format Overflow in syslog() CAPEC-71: Using Unicode Encoding to Bypass Validation Logic Using Unicode Encoding to Bypass Validation Logic CAPEC-73: User-Controlled Filename User-Controlled Filename CAPEC-78: Using Escaped Slashes in Alternate Encoding Using Escaped Slashes in Alternate Encoding CAPEC-79: Using Slashes in Alternate Encoding Using Slashes in Alternate Encoding CAPEC-80: Using UTF-8 Encoding to Bypass Validation Logic Using UTF-8 Encoding to Bypass Validation Logic CAPEC-88: OS Command Injection OS Command Injection CAPEC-92: Forced Integer Overflow Forced Integer Overflow CAPEC-120: Double Encoding Double Encoding CAPEC-182: Flash Injection Flash Injection CAPEC-267: Leverage Alternate Encoding Leverage Alternate Encoding
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.15 }} 0.00%

score

0.51362

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
: