MEDIUM
squid: information disclosure due to incorrect handling of peer responses in tunnel.cc (SQUID-2015:2)
Published Sep 28, 2015
6.8
MEDIUMCVSS 2.0
EPSS 20.84%
Description
Squid before 3.5.6 does not properly handle CONNECT method peer responses when configured with cache_peer, which allows remote attackers to bypass intended restrictions and gain access to a backend proxy via a CONNECT request.
Affected products
No data.
Configuration 1
- 22
Configuration 2
OR
- 7.0
- 8.0
Configuration 3
- ≤ 3.5.2
No data.
Red Hat Enterprise Linux 5
squid
Will not fix
Red Hat Enterprise Linux 6
squid
Will not fix
Red Hat Enterprise Linux 7
squid
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | squid | Will not fix | n/a |
| Red Hat Enterprise Linux 6 | squid | Will not fix | n/a |
| Red Hat Enterprise Linux 7 | squid | Will not fix | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
6.8 MEDIUM NVD
AV:N/AC:M/Au:N/C:P/I:P/A:P
Access Vector Network
Access Complexity Medium
Authentication None
Confidentiality Impact Partial
Integrity Impact Partial
Availability Impact Partial
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
20.84% 0.20844
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
EPSS probability 0.20844
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (52 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 20.84% (0.20844) | 97.48th | v5 (v2026.06.15) |
| Jul 25, 2026 | 20.84% (0.20844) | 97.29th | v5 (v2026.06.15) |
| Jun 15, 2026 | 16.53% (0.16525) | 96.58th | v5 (v2026.06.15) |
| May 13, 2026 | 24.70% (0.24696) | 96.19th | v4 (v2025.03.14) |
| Mar 4, 2026 | 19.75% (0.19753) | 95.32th | v4 (v2025.03.14) |
| Mar 1, 2026 | 44.95% (0.44946) | 97.53th | v4 (v2025.03.14) |
| Feb 4, 2026 | 19.75% (0.19753) | 95.27th | v4 (v2025.03.14) |
| Feb 1, 2026 | 44.95% (0.44946) | 97.50th | v4 (v2025.03.14) |
| Jan 4, 2026 | 19.75% (0.19753) | 95.23th | v4 (v2025.03.14) |
| Jan 1, 2026 | 44.95% (0.44946) | 97.48th | v4 (v2025.03.14) |
| Dec 28, 2025 | 19.75% (0.19753) | 95.24th | v4 (v2025.03.14) |
| Dec 27, 2025 | 26.16% (0.26156) | 96.14th | v4 (v2025.03.14) |
| Dec 4, 2025 | 19.75% (0.19753) | 95.21th | v4 (v2025.03.14) |
| Dec 1, 2025 | 44.95% (0.44946) | 97.45th | v4 (v2025.03.14) |
| Nov 4, 2025 | 19.75% (0.19753) | 95.19th | v4 (v2025.03.14) |
| Nov 1, 2025 | 44.95% (0.44946) | 97.45th | v4 (v2025.03.14) |
| Oct 28, 2025 | 19.75% (0.19753) | 95.18th | v4 (v2025.03.14) |
| Oct 27, 2025 | 26.16% (0.26156) | 96.07th | v4 (v2025.03.14) |
| Oct 4, 2025 | 19.75% (0.19753) | 95.23th | v4 (v2025.03.14) |
| Oct 1, 2025 | 44.95% (0.44946) | 97.51th | v4 (v2025.03.14) |
| Sep 4, 2025 | 26.16% (0.26156) | 96.11th | v4 (v2025.03.14) |
| Sep 1, 2025 | 36.26% (0.36257) | 97.01th | v4 (v2025.03.14) |
| Aug 20, 2025 | 26.16% (0.26156) | 96.08th | v4 (v2025.03.14) |
| Aug 4, 2025 | 33.57% (0.33569) | 96.77th | v4 (v2025.03.14) |
| Aug 1, 2025 | 54.22% (0.54215) | 97.92th | v4 (v2025.03.14) |
| Jul 30, 2025 | 33.57% (0.33569) | 96.76th | v4 (v2025.03.14) |
| Jul 5, 2025 | 21.54% (0.21540) | 95.43th | v4 (v2025.03.14) |
| Jul 1, 2025 | 60.01% (0.60009) | 98.16th | v4 (v2025.03.14) |
| Jun 20, 2025 | 21.54% (0.21540) | 95.39th | v4 (v2025.03.14) |
| Jun 4, 2025 | 15.54% (0.15545) | 94.31th | v4 (v2025.03.14) |
| Jun 1, 2025 | 38.41% (0.38414) | 97.06th | v4 (v2025.03.14) |
| May 9, 2025 | 15.54% (0.15545) | 94.28th | v4 (v2025.03.14) |
| May 5, 2025 | 11.18% (0.11181) | 93.08th | v4 (v2025.03.14) |
| May 1, 2025 | 29.23% (0.29235) | 96.31th | v4 (v2025.03.14) |
| Apr 7, 2025 | 11.18% (0.11181) | 92.87th | v4 (v2025.03.14) |
| Apr 6, 2025 | 29.23% (0.29235) | 96.19th | v4 (v2025.03.14) |
| Apr 3, 2025 | 11.18% (0.11181) | 92.87th | v4 (v2025.03.14) |
| Apr 2, 2025 | 29.23% (0.29235) | 96.19th | v4 (v2025.03.14) |
| Mar 27, 2025 | 11.18% (0.11181) | 92.46th | v4 (v2025.03.14) |
| Mar 25, 2025 | 29.23% (0.29235) | 96.14th | v4 (v2025.03.14) |
| Mar 24, 2025 | 11.18% (0.11181) | 92.84th | v4 (v2025.03.14) |
| Mar 22, 2025 | 29.23% (0.29235) | 96.20th | v4 (v2025.03.14) |
| Mar 21, 2025 | 11.18% (0.11181) | 92.93th | v4 (v2025.03.14) |
| Mar 20, 2025 | 29.23% (0.29235) | 96.20th | v4 (v2025.03.14) |
| Mar 17, 2025 | 11.18% (0.11181) | 92.96th | v4 (v2025.03.14) |
| Dec 17, 2024 | 2.47% (0.02472) | 89.73th | v3 (v2023.03.01) |
| Mar 14, 2024 | 0.93% (0.00933) | 82.63th | v3 (v2023.03.01) |
| Mar 10, 2023 | 0.93% (0.00933) | 80.62th | v3 (v2023.03.01) |
| Mar 7, 2023 | 1.03% (0.01032) | 81.56th | v3 (v2023.03.01) |
| Mar 6, 2023 | 3.78% (0.03779) | 85.48th | v2 (v2022.01.01) |
| Apr 1, 2022 | 3.78% (0.03779) | 84.01th | v2 (v2022.01.01) |
| Feb 4, 2022 | 3.78% (0.03779) | 67.21th | v2 (v2022.01.01) |
References (19)
- http://lists.fedoraproject.org/pipermail/package-announce/2016-May/183598.html vendor-advisoryx_refsource_FEDORA
- http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00010.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00040.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-updates/2016-08/msg00069.html vendor-advisoryx_refsource_SUSE
- http://www.debian.org/security/2015/dsa-3327 vendor-advisoryx_refsource_DEBIAN
- http://www.openwall.com/lists/oss-security/2015/07/06/8 mailing-listx_refsource_MLIST
- http://www.openwall.com/lists/oss-security/2015/07/09/12 mailing-listx_refsource_MLIST
- http://www.openwall.com/lists/oss-security/2015/07/10/2 mailing-listx_refsource_MLIST
- http://www.openwall.com/lists/oss-security/2015/07/17/14 mailing-listx_refsource_MLISTExploit
- http://www.securityfocus.com/bid/75553 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id/1032873 vdb-entryx_refsource_SECTRACK
- http://www.squid-cache.org/Advisories/SQUID-2015_2.txt x_refsource_CONFIRMVendor Advisory
- http://www.squid-cache.org/Versions/v3/3.1/changesets/squid-3.1-10494.patch x_refsource_CONFIRMExploitVendor Advisory
- http://www.squid-cache.org/Versions/v3/3.4/changesets/squid-3.4-13225.patch x_refsource_CONFIRMExploitVendor Advisory
- http://www.squid-cache.org/Versions/v3/3.5/changesets/squid-3.5-13856.patch x_refsource_CONFIRMExploitVendor Advisory
- https://access.redhat.com/security/cve/CVE-2015-5400 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1240741 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2015-5400
- https://www.cve.org/CVERecord?id=CVE-2015-5400
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner mitre
Published Sep 28, 2015
Updated Aug 6, 2024
Reserved Jul 6, 2015
Link CVE-2015-5400
CISA Vulnrichment
Updated n/a