CVE-2023-46846 | Squid: request/response smuggling in http/1.1 and icap

SQUID is vulnerable to HTTP request smuggling, caused by chunked decoder lenience, allows a remote attacker to perform Request/Response smuggling past firewall and frontend security systems.

Published: 2023-11-03 Last update: 2024-12-18 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-46846 is rated Moderate Risk (64.9/100): CVSS Critical severity, with high exploitation likelihood (EPSS 5.25%, 91th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-46846

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 9.58% 5.25% -4.33%
2 2026-06-11 9.82% 9.58% -0.23%
3 2026-05-29 — 9.82% —

Full EPSS history (50 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-46846

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.3 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 4.7 [email protected]
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]

Weakness enumeration for CVE-2023-46846

OS Trackers for CVE-2023-46846

vendor priority summary link
alpine — CVE-2023-46846: 1 source package rows (squid); 62 state rows across 7 repos (3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 5, open 57. https://security.alpinelinux.org/vuln/CVE-2023-46846
debian not yet assigned CVE-2023-46846 not yet assigned priority: Debian including 1 source packages (squid), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2023-46846
redhat high — https://access.redhat.com/security/cve/CVE-2023-46846
suse high — https://www.suse.com/security/cve/CVE-2023-46846/
ubuntu medium CVE-2023-46846 medium priority: Ubuntu including 2 source packages (squid, squid3), 24 status rows across 12 suites (bionic, focal, jammy, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): released 9, DNE 8, ignored 4, needs-triage 3. https://ubuntu.com/security/CVE-2023-46846

Affected software / configurations for CVE-2023-46846

Vendor Product Version Raw CPE
squid-cache squid >= 2.6, < 6.4 cpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux 9.0 cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
redhat enterprise_linux_eus 8.6 cpe:2.3:o:redhat:enterprise_linux_eus:8.6:*:*:*:*:*:*:*
redhat enterprise_linux_eus 8.8 cpe:2.3:o:redhat:enterprise_linux_eus:8.8:*:*:*:*:*:*:*
redhat enterprise_linux_eus 9.0 cpe:2.3:o:redhat:enterprise_linux_eus:9.0:*:*:*:*:*:*:*
redhat enterprise_linux_eus 9.2 cpe:2.3:o:redhat:enterprise_linux_eus:9.2:*:*:*:*:*:*:*
redhat enterprise_linux_for_arm_64 8.0_aarch64 cpe:2.3:o:redhat:enterprise_linux_for_arm_64:8.0_aarch64:*:*:*:*:*:*:*
redhat enterprise_linux_for_ibm_z_systems 8.0_s390x cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:8.0_s390x:*:*:*:*:*:*:*
redhat enterprise_linux_for_power_little_endian 8.0_ppc64le cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:8.0_ppc64le:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 8.2 cpe:2.3:o:redhat:enterprise_linux_server_aus:8.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 8.4 cpe:2.3:o:redhat:enterprise_linux_server_aus:8.4:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 8.6 cpe:2.3:o:redhat:enterprise_linux_server_aus:8.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_aus 9.2 cpe:2.3:o:redhat:enterprise_linux_server_aus:9.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 8.2 cpe:2.3:o:redhat:enterprise_linux_server_tus:8.2:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 8.4 cpe:2.3:o:redhat:enterprise_linux_server_tus:8.4:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 8.6 cpe:2.3:o:redhat:enterprise_linux_server_tus:8.6:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 8.8 cpe:2.3:o:redhat:enterprise_linux_server_tus:8.8:*:*:*:*:*:*:*
redhat enterprise_linux_server_tus 9.2 cpe:2.3:o:redhat:enterprise_linux_server_tus:9.2:*:*:*:*:*:*:*

References for CVE-2023-46846

URL Tags
https://access.redhat.com/errata/RHSA-2023:6266 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:6267 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:6268 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:6748 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:6801 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:6803 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:6804 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:6810 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:7213 Third Party Advisory
https://access.redhat.com/errata/RHSA-2024:11049
https://access.redhat.com/security/cve/CVE-2023-46846 Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2245910 Issue Tracking Third Party Advisory
https://github.com/squid-cache/squid/security/advisories/GHSA-j83v-w3p4-5cqh Vendor Advisory
https://lists.debian.org/debian-lts-announce/2024/01/msg00003.html
https://lists.debian.org/debian-lts-announce/2024/01/msg00008.html
https://security.netapp.com/advisory/ntap-20231130-0002/
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