HIGH
squid: Buffer overflow in reverse-proxy configurations
Published Feb 4, 2020
7.3
HIGHCVSS 3.1
EPSS 71.79%
Description
An issue was discovered in Squid before 4.10. Due to incorrect buffer management, a remote client can cause a buffer overflow in a Squid instance acting as a reverse proxy.
Affected products
No data.
Configuration 1
- < 4.10
Configuration 2
OR
- 16.04
- 18.04
- 19.10
Configuration 4
OR
- 30
- 31
Configuration 5
OR
- 9.0
- 10.0
No data.
Red Hat Enterprise Linux 7
squid-7:3.5.20-17.el7_9.4
Fixed · RHSA-2020:4082
Red Hat Enterprise Linux 8
squid:4-8030020200828070549.30b713e6
Fixed · RHSA-2020:4743
Red Hat Enterprise Linux 5
squid
Not affected
Red Hat Enterprise Linux 6
squid
Will not fix
Red Hat Enterprise Linux 6
squid34
Out of support scope
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 7 | squid-7:3.5.20-17.el7_9.4 | Fixed | RHSA-2020:4082 |
| Red Hat Enterprise Linux 8 | squid:4-8030020200828070549.30b713e6 | Fixed | RHSA-2020:4743 |
| Red Hat Enterprise Linux 5 | squid | Not affected | n/a |
| Red Hat Enterprise Linux 6 | squid | Will not fix | n/a |
| Red Hat Enterprise Linux 6 | squid34 | Out of support scope | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Although the squid packages for Red Hat Enterprise Linux 6 through 8 are affected, they are compiled with FORTIFY_SOURCE, which in this case limits the impact of the buffer overflow to an application termination. This only affects deployments acting as reverse proxy with a http_port 'accel' or 'vhost' (squid 2.x and 3.x) or http_port 'accel' configuration (squid 4.x).
Metrics
No CVSS v4.0 score for this CVE.
7.3 HIGH NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact Low
Integrity Impact Low
Availability Impact Low
1 other source (Red Hat) ▾
5.9 MEDIUM Red Hat
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact None
Availability Impact High
No CVSS v3.0 score for this CVE.
7.5 HIGH NVD
AV:N/AC:L/Au:N/C:P/I:P/A:P
Access Vector Network
Access Complexity Low
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.
71.79% 0.71790
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 4, 2026.
EPSS probability 0.71790
Score over time
2021-2026- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (61 key points)
Flat stretches are collapsed. Showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 4, 2026 | 71.79% (0.71790) | 99.41th | v5 (v2026.06.15) |
| Jun 15, 2026 | 71.79% (0.71790) | 99.34th | v5 (v2026.06.15) |
| Mar 4, 2026 | 46.29% (0.46287) | 97.58th | v4 (v2025.03.14) |
| Mar 1, 2026 | 30.15% (0.30155) | 96.59th | v4 (v2025.03.14) |
| Feb 4, 2026 | 46.29% (0.46287) | 97.55th | v4 (v2025.03.14) |
| Feb 1, 2026 | 30.15% (0.30155) | 96.57th | v4 (v2025.03.14) |
| Jan 4, 2026 | 46.29% (0.46287) | 97.54th | v4 (v2025.03.14) |
| Jan 1, 2026 | 30.15% (0.30155) | 96.54th | v4 (v2025.03.14) |
| Dec 28, 2025 | 46.29% (0.46287) | 97.53th | v4 (v2025.03.14) |
| Dec 27, 2025 | 47.85% (0.47853) | 97.62th | v4 (v2025.03.14) |
| Dec 22, 2025 | 46.29% (0.46287) | 97.52th | v4 (v2025.03.14) |
| Dec 4, 2025 | 43.09% (0.43086) | 97.34th | v4 (v2025.03.14) |
| Dec 1, 2025 | 33.25% (0.33248) | 96.75th | v4 (v2025.03.14) |
| Nov 21, 2025 | 43.09% (0.43086) | 97.33th | v4 (v2025.03.14) |
| Nov 18, 2025 | 90.13% (0.90129) | 99.67th | v4 (v2025.03.14) |
| Nov 4, 2025 | 43.09% (0.43086) | 97.33th | v4 (v2025.03.14) |
| Nov 1, 2025 | 33.25% (0.33248) | 96.72th | v4 (v2025.03.14) |
| Oct 28, 2025 | 43.09% (0.43086) | 97.32th | v4 (v2025.03.14) |
| Oct 27, 2025 | 44.66% (0.44655) | 97.42th | v4 (v2025.03.14) |
| Oct 4, 2025 | 43.09% (0.43086) | 97.40th | v4 (v2025.03.14) |
| Oct 1, 2025 | 33.25% (0.33248) | 96.78th | v4 (v2025.03.14) |
| Sep 5, 2025 | 44.66% (0.44655) | 97.49th | v4 (v2025.03.14) |
| Sep 1, 2025 | 30.72% (0.30722) | 96.60th | v4 (v2025.03.14) |
| Aug 20, 2025 | 44.66% (0.44655) | 97.48th | v4 (v2025.03.14) |
| Aug 4, 2025 | 41.29% (0.41291) | 97.28th | v4 (v2025.03.14) |
| Aug 1, 2025 | 22.41% (0.22412) | 95.63th | v4 (v2025.03.14) |
| Jul 30, 2025 | 41.29% (0.41291) | 97.28th | v4 (v2025.03.14) |
| Jul 18, 2025 | 39.73% (0.39735) | 97.16th | v4 (v2025.03.14) |
| Jul 13, 2025 | 36.60% (0.36599) | 96.95th | v4 (v2025.03.14) |
| Jul 4, 2025 | 40.59% (0.40592) | 97.20th | v4 (v2025.03.14) |
| Jul 1, 2025 | 28.02% (0.28020) | 96.26th | v4 (v2025.03.14) |
| Jun 4, 2025 | 40.59% (0.40592) | 97.17th | v4 (v2025.03.14) |
| Jun 1, 2025 | 28.02% (0.28020) | 96.22th | v4 (v2025.03.14) |
| May 6, 2025 | 40.59% (0.40592) | 97.16th | v4 (v2025.03.14) |
| May 4, 2025 | 46.96% (0.46956) | 97.50th | v4 (v2025.03.14) |
| May 1, 2025 | 36.77% (0.36769) | 96.91th | v4 (v2025.03.14) |
| Apr 17, 2025 | 46.96% (0.46956) | 97.47th | v4 (v2025.03.14) |
| Mar 30, 2025 | 44.44% (0.44439) | 97.29th | v4 (v2025.03.14) |
| Mar 29, 2025 | 50.98% (0.50976) | 96.87th | v4 (v2025.03.14) |
| Mar 17, 2025 | 44.44% (0.44439) | 97.26th | v4 (v2025.03.14) |
| Dec 17, 2024 | 93.70% (0.93704) | 99.33th | v3 (v2023.03.01) |
| May 30, 2024 | 91.91% (0.91909) | 98.92th | v3 (v2023.03.01) |
| Jan 11, 2024 | 93.12% (0.93122) | 98.86th | v3 (v2023.03.01) |
| Dec 26, 2023 | 92.70% (0.92705) | 98.81th | v3 (v2023.03.01) |
| Dec 9, 2023 | 92.87% (0.92870) | 98.80th | v3 (v2023.03.01) |
| Nov 8, 2023 | 92.96% (0.92960) | 98.79th | v3 (v2023.03.01) |
| Jun 24, 2023 | 96.73% (0.96726) | 99.46th | v3 (v2023.03.01) |
| Jun 9, 2023 | 96.86% (0.96857) | 99.51th | v3 (v2023.03.01) |
| May 23, 2023 | 96.68% (0.96680) | 99.42th | v3 (v2023.03.01) |
| May 8, 2023 | 96.60% (0.96600) | 99.37th | v3 (v2023.03.01) |
| Apr 23, 2023 | 96.71% (0.96715) | 99.41th | v3 (v2023.03.01) |
| Apr 7, 2023 | 96.61% (0.96609) | 99.35th | v3 (v2023.03.01) |
| Mar 23, 2023 | 96.68% (0.96679) | 99.37th | v3 (v2023.03.01) |
| Mar 7, 2023 | 96.75% (0.96745) | 99.38th | v3 (v2023.03.01) |
| Mar 6, 2023 | 2.69% (0.02686) | 82.85th | v2 (v2022.01.01) |
| Apr 1, 2022 | 2.69% (0.02686) | 81.17th | v2 (v2022.01.01) |
| Feb 4, 2022 | 23.44% (0.23437) | 94.77th | v2 (v2022.01.01) |
| Feb 3, 2022 | 13.21% (0.13208) | 89.07th | v1 |
| Jan 6, 2022 | 13.21% (0.13208) | 88.94th | v1 |
| Sep 1, 2021 | 3.28% (0.03281) | 81.60th | v1 |
| Apr 14, 2021 | 3.28% (0.03281) | 0.00th | v1 |
Weaknesses (3)
References (19)
- http://lists.opensuse.org/opensuse-security-announce/2020-03/msg00012.html vendor-advisoryx_refsource_SUSEMailing ListThird Party Advisory
- http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00010.html vendor-advisoryx_refsource_SUSEMailing ListThird Party Advisory
- http://www.squid-cache.org/Advisories/SQUID-2020_1.txt x_refsource_MISCVendor Advisory
- http://www.squid-cache.org/Versions/v3/3.5/changesets/SQUID-2020_1.patch x_refsource_MISCPatchVendor Advisory
- http://www.squid-cache.org/Versions/v3/3.5/changesets/squid-3.5-8e657e835965c3a011375feaa0359921c5b3e2dd.patch x_refsource_MISCPatchVendor Advisory
- http://www.squid-cache.org/Versions/v4/changesets/SQUID-2020_1.patch x_refsource_MISCPatchVendor Advisory
- http://www.squid-cache.org/Versions/v4/changesets/squid-4-b3a0719affab099c684f1cd62b79ab02816fa962.patch x_refsource_MISCPatchVendor Advisory
- http://www.squid-cache.org/Versions/v4/changesets/squid-4-d8e4715992d0e530871519549add5519cbac0598.patch x_refsource_MISCPatchVendor Advisory
- https://access.redhat.com/security/cve/CVE-2020-8450 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1798552 Issue Tracking
- https://lists.debian.org/debian-lts-announce/2020/07/msg00009.html mailing-listx_refsource_MLISTMailing ListThird Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/G6W2IQ7QV2OGREFFUBNVZIDD3RJBDE4R/ vendor-advisoryx_refsource_FEDORA
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TSU6SPANL27AGK5PCGBJOKG4LUWA555J/ vendor-advisoryx_refsource_FEDORA
- https://nvd.nist.gov/vuln/detail/CVE-2020-8450
- https://security.gentoo.org/glsa/202003-34 vendor-advisoryx_refsource_GENTOOThird Party Advisory
- https://security.netapp.com/advisory/ntap-20210304-0002/ x_refsource_CONFIRMThird Party Advisory
- https://usn.ubuntu.com/4289-1/ vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2020-8450
- https://www.debian.org/security/2020/dsa-4682 vendor-advisoryx_refsource_DEBIANThird Party Advisory
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner mitre
Published Feb 4, 2020
Updated Aug 4, 2024
Reserved Jan 30, 2020
Link CVE-2020-8450
CISA Vulnrichment
Updated n/a