Squid vulnerable to heap corruption in ESI assign
Published Jun 25, 2024
6.3
MEDIUMCVSS 3.1
EPSS 6.25%
Description
Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to an Out-of-bounds Write error when assigning ESI variables, Squid is susceptible to a Memory Corruption error. This error can lead to a Denial of Service attack.
Affected products
-
- Version >= 3.0, <= 3.5.28StatusaffectedConstraints-
- Version >= 4.0, <= 4.16StatusaffectedConstraints-
- Version >= 5.0, <= 5.9StatusaffectedConstraints-
- Version >= 6.0, <= 6.9StatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Squid-Cache | Squid | n/a |
|
- ≥ 3.0 · < 6.10
No data.
Red Hat Enterprise Linux 9
squid-7:5.5-13.el9_4
Fixed · RHSA-2024:4861
Red Hat Enterprise Linux 9.2 Extended Update Support
squid-7:5.5-5.el9_2.7
Fixed · RHSA-2024:5906
Red Hat Enterprise Linux 10
squid
Not affected
Red Hat Enterprise Linux 6
squid
Out of support scope
Red Hat Enterprise Linux 6
squid34
Out of support scope
Red Hat Enterprise Linux 7
squid
Out of support scope
Red Hat Enterprise Linux 8
squid:4/squid
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 9 | squid-7:5.5-13.el9_4 | Fixed | RHSA-2024:4861 |
| Red Hat Enterprise Linux 9.2 Extended Update Support | squid-7:5.5-5.el9_2.7 | Fixed | RHSA-2024:5906 |
| Red Hat Enterprise Linux 10 | squid | Not affected | n/a |
| Red Hat Enterprise Linux 6 | squid | Out of support scope | n/a |
| Red Hat Enterprise Linux 6 | squid34 | Out of support scope | n/a |
| Red Hat Enterprise Linux 7 | squid | Out of support scope | n/a |
| Red Hat Enterprise Linux 8 | squid:4/squid | Will not fix | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Squid as shipped in Red Hat Enterprise Linux 8 and 9 is vulnerable to this vulnerability as the ESI support is enabled by default. This flaw requires Squid to be in a reverse proxy configuration and using an ESI variable with non ASCII characters, allowing a trusted server to cause a denial of service. For these reasons, this flaw was rated with a Moderate severity.
Red Hat mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
PartialDecision
n/aAssessed Jun 26, 2024 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2024–2026- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (11 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 6.25% (0.06255) | 93.35th | v5 (v2026.06.15) |
| Jun 15, 2026 | 6.25% (0.06255) | 92.63th | v5 (v2026.06.15) |
| Nov 21, 2025 | 1.34% (0.01343) | 79.44th | v4 (v2025.03.14) |
| Nov 18, 2025 | 9.88% (0.09879) | 92.20th | v4 (v2025.03.14) |
| Aug 3, 2025 | 0.84% (0.00844) | 73.95th | v4 (v2025.03.14) |
| Apr 15, 2025 | 2.39% (0.02387) | 84.05th | v4 (v2025.03.14) |
| Mar 30, 2025 | 4.09% (0.04091) | 87.50th | v4 (v2025.03.14) |
| Mar 29, 2025 | 7.53% (0.07534) | 86.08th | v4 (v2025.03.14) |
| Mar 17, 2025 | 3.60% (0.03605) | 86.98th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.04% (0.00045) | 17.70th | v3 (v2023.03.01) |
| Jun 26, 2024 | 0.04% (0.00043) | 9.08th | v3 (v2023.03.01) |
References (9)
- https://access.redhat.com/security/cve/CVE-2024-37894 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2294353 Issue Tracking
- https://github.com/squid-cache/squid/commit/f411fe7d75197852f0e5ee85027a06d58dd8df4c.patch x_refsource_MISCPatch
- https://github.com/squid-cache/squid/security/advisories/GHSA-wgvf-q977-9xjg x_refsource_CONFIRMPatchVendor Advisory
- https://lists.debian.org/debian-lts-announce/2025/03/msg00009.html
- https://megamansec.github.io/Squid-Security-Audit/esi-underflow.html
- https://nvd.nist.gov/vuln/detail/CVE-2024-37894
- https://security.netapp.com/advisory/ntap-20240719-0001/ Third Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2024-37894
Change history (0)
No recorded changes yet.