CVE-2023-46847 | Squid: denial of service in http digest authentication

Squid is vulnerable to a Denial of Service, where a remote attacker can perform buffer overflow attack by writing up to 2 MB of arbitrary data to heap memory when Squid is configured to accept HTTP Digest Authentication.

Published: 2023-11-03 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-46847 is rated Moderate Risk (63.4/100): CVSS High severity, with high exploitation likelihood (EPSS 38.21%, 97th 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-2023-46847

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 2026-03-21 44.74% 38.21% -6.53%
2 2026-01-13 44.64% 44.74% +0.09%
3 2025-12-28 — 44.64% —

Full EPSS history (37 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-46847

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.6 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H 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:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 4.7 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 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:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2023-46847

OS Trackers for CVE-2023-46847

vendor priority summary link
alpine — CVE-2023-46847: 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-2023-46847
debian not yet assigned CVE-2023-46847 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-2023-46847
redhat critical — https://access.redhat.com/security/cve/CVE-2023-46847
suse high — https://www.suse.com/security/cve/CVE-2023-46847/
ubuntu medium CVE-2023-46847 medium priority: Ubuntu including 2 source packages (squid, squid3), 16 status rows across 8 suites (bionic, focal, jammy, lunar, mantic, trusty, upstream, xenial): released 7, DNE 4, ignored 4, needs-triage 1. https://ubuntu.com/security/CVE-2023-46847

Affected software / configurations for CVE-2023-46847

Vendor Product Version Raw CPE
squid-cache squid >= 3.2.0.1, < 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 7.0 cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
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:*:*:*:*:*:*:*
redhat enterprise_linux_workstation 7.0 cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*

References for CVE-2023-46847

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-2023:6805 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:6810 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:6882 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:6884 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:7213 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:7576 Third Party Advisory
https://access.redhat.com/errata/RHSA-2023:7578 Third Party Advisory
https://access.redhat.com/security/cve/CVE-2023-46847 Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2245916 Issue Tracking Third Party Advisory
https://github.com/squid-cache/squid/security/advisories/GHSA-phqj-m8gv-cq4g Vendor Advisory
https://lists.debian.org/debian-lts-announce/2024/01/msg00003.html
https://security.netapp.com/advisory/ntap-20231130-0002/
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